Mauricio Yucra garrido - Academia.edu (original) (raw)
Papers by Mauricio Yucra garrido
Cardiovascular Reviews Reports, 2003
The impact that left ventricular assist devices (LVADs) have on the remodeling process has been t... more The impact that left ventricular assist devices (LVADs) have on the remodeling process has been the subject of numerous studies. The impact of these devices has been investigated with regard to chamber geometry, calcium regulation, the extracellular matrix, and cardiac myocyte properties. Reverse remodeling that is seen in these patients stems from the LVAD unloading the ventricle. Passive ventricular constraint devices are relatively new. The manner in which they function differs from LVADs. Also, passive ventricular constraint devices are intended for a different subpopulation of heart failure patients; however, like LVADs, they appear to reverse the remodeling process and may help prevent certain patients from ever requiring an LVAD or transplantation at a later date.
Current Cardiology Reports, 2002
Medical therapy for heart failure is quickly advancing, but long-term survival unfortunately rema... more Medical therapy for heart failure is quickly advancing, but long-term survival unfortunately remains poor. New surgical techniques seek to halt and reverse the progression of heart failure. Positron emission tomography has refined patient selection techniques for coronary artery bypass grafting in the failing heart. Left ventricular (LV) remodeling surgery and new devices change the shape of the LV and decrease LV wall stress. Passive restraint devices improve systolic function by preventing ventricular dilatation. LV assist devices have proven to be effective and provide a significantly higher 1-year survival rate when compared with maximal medical therapy. New ideas and devices are defining a new role for surgical treatment of the aging population of the United States and may provide the answer to long-term management of heart failure.
Aging, Heart Disease, and Its Management, 2002
The Heart Surgery Forum, 2006
Over the past several years, pulmonary vein isolation for the treatment of atrial fibrillation ha... more Over the past several years, pulmonary vein isolation for the treatment of atrial fibrillation has gained significant popularity. This study was undertaken to evaluate a novel radiofrequency (RF)-enabled clamp system designed to create transmural lesions epicardially on the beating heart using bipolar RF. A set of differently shaped clamps modified to deliver bipolar RF energy were used to create a series of lesions in a beating heart canine model. The pulmonary veins and atrial appendages of 6 dogs were electrically isolated using bipolar RF energy. The right and left atrial appendages served as controls for the right and left pulmonary veins, respectively. Temperature-controlled RF energy was delivered to maintain a tissue temperature of 80 degrees C for 15 seconds. Electrical isolation was assessed acutely and after 4 weeks by a bipolar pacing protocol. A total of 24 circumferential lesions were created. By pacing analysis, 100% (24/24) of these lesions were electrically isolated acutely and 95% (19/20) were still isolated 4 weeks later. At 4 weeks, 92% (22/24) of lesions were transmural by histologic analysis, and 96% (23/24) demonstrated endocardial continuity. One animal experienced a fatal cardiac arrhythmia during initiation of the post-survival procedure, prior to electrophysiologic evaluation, accounting for the reduced number of potential electrically isolated lesions. Bipolar RF ablation utilizing a novel bipolar RF clamp device results in electrical isolation and histologic transmurality in an off-pump epicardial model.
The Heart Surgery Forum, 2006
Background. A risk factor summation score was previously validated to successfully predict surviv... more Background. A risk factor summation score was previously validated to successfully predict survival after insertion of a left ventricular assist device (LVAD). We investigated whether this scoring system also predicts clinical outcomes after eventual heart transplantation in LVAD recipients. Methods. A retrospective review was performed on 153 consecutive patients who received an LVAD as a bridge to transplantation at 2 large-volume centers from 1996 to 2003. The scoring system was used to designate low-and highscoring groups. Results. Thirty-day mortality and 5-year survival after transplantation were equivalent between groups (4.46% versus 7.32% and 76% versus 70%, respectively). No difference was seen in length of posttransplantation ventilator dependence (2.83 ± 0.49 versus 3.3 ± 0.72 days) or intensive care unit monitoring (6.38 ± 0.77 versus 6.97 ± 1.1 days). However, low-scoring patients had a significantly decreased duration of inotrope support (5.57 ± 0.45 versus 7.74 ± 1.0 days, P = .035). Conclusion. A risk factor summation score may predict which LVAD patients will require prolonged inotropic support following heart transplantation. However, survival in high-risk (elevated score) LVAD patients following heart transplantation is comparable to low-risk groups, favoring the continued practice of LVAD implantation as a bridge to transplantation even in high-risk patients.
The Journal of Thoracic and Cardiovascular Surgery, 2007
Objectives: (1) To examine the interaction of donor age with ischemic time and their effect on su... more Objectives: (1) To examine the interaction of donor age with ischemic time and their effect on survival and (2) to define ranges of ischemic time associated with differences in survival. Methods: The United Network for Organ Sharing provided de-identified patientlevel data. The study population included 33,640 recipients undergoing heart transplantation between October 1, 1987, and December 31, 2004. Recipients were divided by donor age into terciles: 0 to 19 years (n ϭ 10,814; 32.1%), 20 to 33 years (11,410, 33.9%), and 34 years or more (11,416, 33.9%). Kaplan-Meier survival functions and Cox regression were used for time-to-event analysis. Receiver operating characteristic curves and stratum-specific likelihood ratios were generated to compare 5-year survival at various thresholds for ischemic time. Results: In univariate Cox proportional hazards regression, the effect of ischemic time on survival varied by donor age tercile: 0 to 19 years (P ϭ .141), 20 to 33 years (P Ͻ .001), and 34 years or more (P Ͻ .001). These relationships persisted in multivariable regression. Threshold analysis generated a single stratum (0.37-12.00 hours) in the 0-to 19-year-old group with a median survival of 11.4 years. However, in the 20-to 33-year-old-group, 3 strata were generated: 0.00 to 3.49 hours (limited), 3.50 to 6.24 hours (prolonged), and 6.25 hours or more (extended), with median survivals of 10.6, 9.9, and 7.3 years, respectively. Likewise, 3 strata were generated in the group aged 34 years or more: 0.00 to 3.49 (limited), 3.50 to 5.49 (prolonged), and 5.50 or more (extended), with median survivals of 9.1, 8.5, and 6.3 years, respectively. Conclusions: The effect of ischemic time on survival after heart transplantation is dependent on donor age, with greater tolerance for prolonged ischemic times among grafts from younger donors. Both donor age and anticipated ischemic time must be considered when assessing a potential donor.
Journal of the American College of Cardiology, 2003
Background: Recent studies suggest that atrial fibrillation (AF) originates within the left atriu... more Background: Recent studies suggest that atrial fibrillation (AF) originates within the left atrium (LA) near the pulmonary veins, and that isolation of this region may successfully cure AF. Methods: Patients with AF of at least 6 months duration underwent surgical atrial fibrillation ablation (SAFA) as a concomitant cardiac surgical procedure. Lesions
Journal of the American College of Cardiology, 2003
Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA)... more Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA) and longer with an Bmm-tip cath. The cave-tricuspid isthmus (CTl) length and the anatomy may influence RFA in pts with atrial flutter (AFL). Objectives. This prospective study on AFL RFA was: (1) to randomly compare the efficacy of an Bmm-tip cath or a cRFA in pts with CTI > 35 mm; (2)to evaluate the impact of CTI morphology and length. Methods. During 9 months, 115 pts with AFL were eligible; 101 pts (66+/m12 years; 12 females) accepted the protocol and underwent an isthmogram. Groups (gps) were considered in the CTI length (short ~35 mm or long > 35 mm) and CTI anatomy: straight; concave or with a pouchlike recess. An B-mm-tip cath was used for pts with a short CTI. The end-point was a bi-directional block. Results: history of AFib(41/101), structural heart disease (37/101), LV EF (59*12%), CTI dimension (34*6 mm), 60 pts with short CTI. bi-directional block (98%), mean RF application (lP.6+13 min), mean fluoroscopic time (14t13 min) and RF failure (2%). There were no complications.ln pts with long CTI (n=41). 22 patients were randomly assigned in the a-mm gp and 19 pts in the c
Journal of the American College of Cardiology, 2003
Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA)... more Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA) and longer with an Bmm-tip cath. The cave-tricuspid isthmus (CTl) length and the anatomy may influence RFA in pts with atrial flutter (AFL). Objectives. This prospective study on AFL RFA was: (1) to randomly compare the efficacy of an Bmm-tip cath or a cRFA in pts with CTI > 35 mm; (2)to evaluate the impact of CTI morphology and length. Methods. During 9 months, 115 pts with AFL were eligible; 101 pts (66+/m12 years; 12 females) accepted the protocol and underwent an isthmogram. Groups (gps) were considered in the CTI length (short ~35 mm or long > 35 mm) and CTI anatomy: straight; concave or with a pouchlike recess. An B-mm-tip cath was used for pts with a short CTI. The end-point was a bi-directional block. Results: history of AFib(41/101), structural heart disease (37/101), LV EF (59*12%), CTI dimension (34*6 mm), 60 pts with short CTI. bi-directional block (98%), mean RF application (lP.6+13 min), mean fluoroscopic time (14t13 min) and RF failure (2%). There were no complications.ln pts with long CTI (n=41). 22 patients were randomly assigned in the a-mm gp and 19 pts in the c
Journal of the American College of Cardiology, 2004
Journal of Cardiac Surgery, 2004
As less complex modifications of the Maze procedure have been developed, a number of energy sourc... more As less complex modifications of the Maze procedure have been developed, a number of energy sources have been introduced to facilitate the creation of electrically isolating lesions within the atria. These include cryoablation, radiofrequency, microwave, laser, and focused ultrasound. Although each of these sources works slightly differently, the goal of all thermal sources is to heat tissue to a temperature (50 • C) above which irreversible electrical isolation occurs. These sources have been utilized both endocardially in arrested heart procedures as well as epicardially in the beating heart setting. There are several obstacles to the use of these sources epicardially, mostly related to the heat sink effect of endocardial blood. Several recent modifications have been introduced that will hopefully increase the efficacy of these sources in beating heart applications.
Journal of Cardiac Surgery, 2004
In the last several years, a number of procedures have been conceived that have attempted to trea... more In the last several years, a number of procedures have been conceived that have attempted to treat atrial fibrillation (AF) by creating a limited set of lesions modeled after those of the Maze operation. These lesions have been created by a variety of means, including the traditional cut-and-sew method, but also by nonincisional techniques. These have included cryoablation as well as several thermal techniques, using radiofrequency, microwave, laser, and focused ultrasound energy. One reason for the development of these nonincisional techniques has been the desire to develop less invasive operations for the treatment of AF. The specific goal of our center has been to utilize these energy sources as well as other minimally invasive tools, such as surgical robots, to develop a closed chest, off-pump procedure for AF. The development of such a procedure is outlined in this article.
Journal of Cardiac Surgery, 2006
Background: The Maze III procedure is an effective surgical treatment for atrial fibrillation (AF... more Background: The Maze III procedure is an effective surgical treatment for atrial fibrillation (AF). However, it is not widely applied due to its complexity, increased operative times, and the risk of bleeding. Various energy sources have been introduced to simplify the traditional "cut and sew" approach. Methods: This study involves patients undergoing surgical atrial fibrillation ablation (SAFA) at a single institution from 1999 to 2005. Type of concomitant procedures, preoperative clinical characteristics, and chronicity of AF were evaluated in overall patient population. Parameters including surgical approach, lesion pattern, and energy source used were collected intraoperatively. Clinical outcomes examined were postoperative rhythm success, stroke, early mortality, and long-term survival. Results: Three hundred thirty-nine patients were identified. Three hundred twenty-eight (96.8%) patients had associated cardiac disease and underwent concomitant procedures; 75.8% of patients had persistent AF. Energy sources used were microwave (49.8%), radiofrequency (42.2%), and laser (8.0%). In 41.9% of cases a pulmonary vein encircling lesion was the only lesion created. Combination lesion sets were performed in the remaining cases. Rhythm success rates at 3, 6, 12, and 24 months were 74.1%, 68.2%, 74.5%, and 71.1%, respectively. Patients who underwent surgical removal of left atrial appendage by means of stapling or simple excision had no early postoperative stroke. Early mortality was 4.9%. Postoperative survival rates at 1, 3, and 5 years were 89.6%, 83.1%, and 78.0%. Conclusions: Surgical ablation of atrial fibrillation is a safe and effective procedure in restoring sinus rhythm with excellent postoperative survival rates. Further advancements in the field will eventually result in minimally invasive procedures with higher success rates.
Congestive Heart Failure, 2003
A wide array of surgical options are currently available for the treatment of congestive heart fa... more A wide array of surgical options are currently available for the treatment of congestive heart failure ranging from traditional coronary artery bypass grafting to total artificial heart implantation. The indications for each procedure depend on the severity of disease and the individual patients desires. Some surgical options are indicated for patients with moderate disease and prevent worsening heart failure, whereas other procedures are limited to patients who will only survive with high-risk surgery. Ongoing technologic advances are increasing the number of patients that benefit from the reparative surgical treatment of congestive heart failure.
The Annals of Thoracic Surgery, 2003
Background. Inhibition of angiotensin-converting enzyme (ACE) predisposes patients to vasodilator... more Background. Inhibition of angiotensin-converting enzyme (ACE) predisposes patients to vasodilatory hypotension after cardiopulmonary bypass (CPB). This hypotension has been correlated with arginine vasopressin deficiency and can be corrected by its replacement. In patients receiving ACE inhibition, we investigated whether initiation of vasopressin before CPB would diminish post-CPB hypotension and catecholamine use by avoiding vasopressin deficiency. Methods. Cardiac surgical patients on ACE inhibitor therapy were randomized to receive vasopressin (0.03 U/min) (n ؍ 13) or an equal volume of normal saline (n ؍ 14) starting 20 minutes before CPB. Results. Vasopressin did not change pre-CPB mean arterial pressure or pulmonary artery pressure. After CPB, the vasopressin group had a lower peak norepinephrine dose than the placebo group (4.6 ؎ 2.5 versus 7.3 ؎ 3.5 g/min, p ؍ 0.03), a shorter period on catecholamines (5 ؎ 6 versus 11 ؎ 7 hours, p ؍ 0.03), fewer hypotensive episodes (1 ؎ 1 versus 4 ؎ 2, p < 0.01), and a shorter intensive care unit length of stay (1.2 ؎ 0.4 versus 2.1 ؎ 1.4 days, p ؍ 0.03). Conclusions. In this cohort, prophylactic administration of vasopressin, at a dose without a vasopressor effect pre-CPB, reduced post-CPB hypotension and vasoconstrictor requirements, and was associated with a shorter intensive care unit stay.
The Annals of Thoracic Surgery, 2004
Background. Minimally invasive cardiac surgery has emerged as an alternative to conventional, ope... more Background. Minimally invasive cardiac surgery has emerged as an alternative to conventional, open surgery. Although most studies of robotically assisted cardiac surgery have reported morbidity and mortality, few have addressed outcome measures, such as pain and quality of life, which was the aim of this study. Methods. Eleven patients with atrial septal defects (ASD), and five patients with patent foramen ovale, underwent repair using the Da Vinci system (Intuitive Surgical, Mountain View, CA). The Medical Outcomes Study Short Form Survey (SF-36), along with two additional questions, were administered to these patients on postoperative day 30, along with a similar number of patients who underwent ASD repair by minithoracotomy or sternotomy. Quality of life endpoints included bodily pain, vitality, mental health, general health, physical function, and social function. Results. Robotic patients demonstrated significantly higher scores in 6 of the eight variables (p < 0.05). There was no significant difference in intensive care unit or overall hospital stay among the groups (p ؍ NS). Robotic patients returned to work after 40.2 ؎ 30.2 days, minithoracotomy patients after 45.6 ؎ 27.9 days, and sternotomy patients after 51.7 ؎ 40.2 days (p ؍ 0.767). There were no significant differences in SF-36 scores between patients who underwent mini-thoracotomy and sternotomy approaches. Conclusions. Closure of an ASD can be performed safely and effectively via an endoscopic approach. Robotic technology minimized the degree of invasiveness, hastened postoperative recovery, and improved quality of life, although length of hospital stay was unchanged.
The Annals of Thoracic Surgery, 2004
Background. The edge-to-edge mitral valve repair, first described by Alfieri in 1995 treats mitra... more Background. The edge-to-edge mitral valve repair, first described by Alfieri in 1995 treats mitral regurgitation when standard reparative techniques are difficult, unlikely to succeed, or have failed. This study examines one institution's medium-term experience with this procedure. Methods. This study involved patients undergoing edge-to-edge mitral valve repair at a single institution from 1997 to 2003. Preoperative and postoperative echocardiograms were compared. Postoperative morbidity was examined including need for reoperation and longterm medical management. Thirty-day survival and longterm actuarial survival were also determined. Results. Seventy-one patients comprised this study. Mitral regurgitation on echocardiogram went from 3.43 ؎ 0.86 to 0.39 ؎ 0.61 (p < 0.001) following repair. Thirty-day mortality was 3 of 71 (4.2%) patients. Actuarial survivals at 24 and 60 months were 84.5% and 58.3%, respectively; adjusted excluding noncardiac death they were 89.5% and 82.3%, respectively. Forty (56.3%) patients had concomitant ring placement and experienced similar survival to those repaired with the bow-tie stitch alone. Home telephone follow-up was conducted, and current medical therapy was determined on 51 patients; 59% were on a -blocker, 31% were on an angiotensinconverting enzyme (ACE) inhibitor, 27% were on a diuretic, and 22% were on digoxin. All were New York Heart Association (NYHA) class I or II. Three patients (4.2%) underwent mitral valve reoperation after a mean of 299 ؎ 429 days. In no case did the bow-tie suture rupture. Conclusions. Edge-to-edge mitral valve repair is a valuable tool in the armamentarium available to treat complex cases of mitral insufficiency or as an adjunct to standard repair techniques that fail to achieve an acceptable result.
Cardiovascular Reviews Reports, 2003
The impact that left ventricular assist devices (LVADs) have on the remodeling process has been t... more The impact that left ventricular assist devices (LVADs) have on the remodeling process has been the subject of numerous studies. The impact of these devices has been investigated with regard to chamber geometry, calcium regulation, the extracellular matrix, and cardiac myocyte properties. Reverse remodeling that is seen in these patients stems from the LVAD unloading the ventricle. Passive ventricular constraint devices are relatively new. The manner in which they function differs from LVADs. Also, passive ventricular constraint devices are intended for a different subpopulation of heart failure patients; however, like LVADs, they appear to reverse the remodeling process and may help prevent certain patients from ever requiring an LVAD or transplantation at a later date.
Current Cardiology Reports, 2002
Medical therapy for heart failure is quickly advancing, but long-term survival unfortunately rema... more Medical therapy for heart failure is quickly advancing, but long-term survival unfortunately remains poor. New surgical techniques seek to halt and reverse the progression of heart failure. Positron emission tomography has refined patient selection techniques for coronary artery bypass grafting in the failing heart. Left ventricular (LV) remodeling surgery and new devices change the shape of the LV and decrease LV wall stress. Passive restraint devices improve systolic function by preventing ventricular dilatation. LV assist devices have proven to be effective and provide a significantly higher 1-year survival rate when compared with maximal medical therapy. New ideas and devices are defining a new role for surgical treatment of the aging population of the United States and may provide the answer to long-term management of heart failure.
Aging, Heart Disease, and Its Management, 2002
The Heart Surgery Forum, 2006
Over the past several years, pulmonary vein isolation for the treatment of atrial fibrillation ha... more Over the past several years, pulmonary vein isolation for the treatment of atrial fibrillation has gained significant popularity. This study was undertaken to evaluate a novel radiofrequency (RF)-enabled clamp system designed to create transmural lesions epicardially on the beating heart using bipolar RF. A set of differently shaped clamps modified to deliver bipolar RF energy were used to create a series of lesions in a beating heart canine model. The pulmonary veins and atrial appendages of 6 dogs were electrically isolated using bipolar RF energy. The right and left atrial appendages served as controls for the right and left pulmonary veins, respectively. Temperature-controlled RF energy was delivered to maintain a tissue temperature of 80 degrees C for 15 seconds. Electrical isolation was assessed acutely and after 4 weeks by a bipolar pacing protocol. A total of 24 circumferential lesions were created. By pacing analysis, 100% (24/24) of these lesions were electrically isolated acutely and 95% (19/20) were still isolated 4 weeks later. At 4 weeks, 92% (22/24) of lesions were transmural by histologic analysis, and 96% (23/24) demonstrated endocardial continuity. One animal experienced a fatal cardiac arrhythmia during initiation of the post-survival procedure, prior to electrophysiologic evaluation, accounting for the reduced number of potential electrically isolated lesions. Bipolar RF ablation utilizing a novel bipolar RF clamp device results in electrical isolation and histologic transmurality in an off-pump epicardial model.
The Heart Surgery Forum, 2006
Background. A risk factor summation score was previously validated to successfully predict surviv... more Background. A risk factor summation score was previously validated to successfully predict survival after insertion of a left ventricular assist device (LVAD). We investigated whether this scoring system also predicts clinical outcomes after eventual heart transplantation in LVAD recipients. Methods. A retrospective review was performed on 153 consecutive patients who received an LVAD as a bridge to transplantation at 2 large-volume centers from 1996 to 2003. The scoring system was used to designate low-and highscoring groups. Results. Thirty-day mortality and 5-year survival after transplantation were equivalent between groups (4.46% versus 7.32% and 76% versus 70%, respectively). No difference was seen in length of posttransplantation ventilator dependence (2.83 ± 0.49 versus 3.3 ± 0.72 days) or intensive care unit monitoring (6.38 ± 0.77 versus 6.97 ± 1.1 days). However, low-scoring patients had a significantly decreased duration of inotrope support (5.57 ± 0.45 versus 7.74 ± 1.0 days, P = .035). Conclusion. A risk factor summation score may predict which LVAD patients will require prolonged inotropic support following heart transplantation. However, survival in high-risk (elevated score) LVAD patients following heart transplantation is comparable to low-risk groups, favoring the continued practice of LVAD implantation as a bridge to transplantation even in high-risk patients.
The Journal of Thoracic and Cardiovascular Surgery, 2007
Objectives: (1) To examine the interaction of donor age with ischemic time and their effect on su... more Objectives: (1) To examine the interaction of donor age with ischemic time and their effect on survival and (2) to define ranges of ischemic time associated with differences in survival. Methods: The United Network for Organ Sharing provided de-identified patientlevel data. The study population included 33,640 recipients undergoing heart transplantation between October 1, 1987, and December 31, 2004. Recipients were divided by donor age into terciles: 0 to 19 years (n ϭ 10,814; 32.1%), 20 to 33 years (11,410, 33.9%), and 34 years or more (11,416, 33.9%). Kaplan-Meier survival functions and Cox regression were used for time-to-event analysis. Receiver operating characteristic curves and stratum-specific likelihood ratios were generated to compare 5-year survival at various thresholds for ischemic time. Results: In univariate Cox proportional hazards regression, the effect of ischemic time on survival varied by donor age tercile: 0 to 19 years (P ϭ .141), 20 to 33 years (P Ͻ .001), and 34 years or more (P Ͻ .001). These relationships persisted in multivariable regression. Threshold analysis generated a single stratum (0.37-12.00 hours) in the 0-to 19-year-old group with a median survival of 11.4 years. However, in the 20-to 33-year-old-group, 3 strata were generated: 0.00 to 3.49 hours (limited), 3.50 to 6.24 hours (prolonged), and 6.25 hours or more (extended), with median survivals of 10.6, 9.9, and 7.3 years, respectively. Likewise, 3 strata were generated in the group aged 34 years or more: 0.00 to 3.49 (limited), 3.50 to 5.49 (prolonged), and 5.50 or more (extended), with median survivals of 9.1, 8.5, and 6.3 years, respectively. Conclusions: The effect of ischemic time on survival after heart transplantation is dependent on donor age, with greater tolerance for prolonged ischemic times among grafts from younger donors. Both donor age and anticipated ischemic time must be considered when assessing a potential donor.
Journal of the American College of Cardiology, 2003
Background: Recent studies suggest that atrial fibrillation (AF) originates within the left atriu... more Background: Recent studies suggest that atrial fibrillation (AF) originates within the left atrium (LA) near the pulmonary veins, and that isolation of this region may successfully cure AF. Methods: Patients with AF of at least 6 months duration underwent surgical atrial fibrillation ablation (SAFA) as a concomitant cardiac surgical procedure. Lesions
Journal of the American College of Cardiology, 2003
Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA)... more Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA) and longer with an Bmm-tip cath. The cave-tricuspid isthmus (CTl) length and the anatomy may influence RFA in pts with atrial flutter (AFL). Objectives. This prospective study on AFL RFA was: (1) to randomly compare the efficacy of an Bmm-tip cath or a cRFA in pts with CTI > 35 mm; (2)to evaluate the impact of CTI morphology and length. Methods. During 9 months, 115 pts with AFL were eligible; 101 pts (66+/m12 years; 12 females) accepted the protocol and underwent an isthmogram. Groups (gps) were considered in the CTI length (short ~35 mm or long > 35 mm) and CTI anatomy: straight; concave or with a pouchlike recess. An B-mm-tip cath was used for pts with a short CTI. The end-point was a bi-directional block. Results: history of AFib(41/101), structural heart disease (37/101), LV EF (59*12%), CTI dimension (34*6 mm), 60 pts with short CTI. bi-directional block (98%), mean RF application (lP.6+13 min), mean fluoroscopic time (14t13 min) and RF failure (2%). There were no complications.ln pts with long CTI (n=41). 22 patients were randomly assigned in the a-mm gp and 19 pts in the c
Journal of the American College of Cardiology, 2003
Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA)... more Radiofrequency ablation (RFA) lesions are expected to be deeper with a cooled-tip RFA cath (cRFA) and longer with an Bmm-tip cath. The cave-tricuspid isthmus (CTl) length and the anatomy may influence RFA in pts with atrial flutter (AFL). Objectives. This prospective study on AFL RFA was: (1) to randomly compare the efficacy of an Bmm-tip cath or a cRFA in pts with CTI > 35 mm; (2)to evaluate the impact of CTI morphology and length. Methods. During 9 months, 115 pts with AFL were eligible; 101 pts (66+/m12 years; 12 females) accepted the protocol and underwent an isthmogram. Groups (gps) were considered in the CTI length (short ~35 mm or long > 35 mm) and CTI anatomy: straight; concave or with a pouchlike recess. An B-mm-tip cath was used for pts with a short CTI. The end-point was a bi-directional block. Results: history of AFib(41/101), structural heart disease (37/101), LV EF (59*12%), CTI dimension (34*6 mm), 60 pts with short CTI. bi-directional block (98%), mean RF application (lP.6+13 min), mean fluoroscopic time (14t13 min) and RF failure (2%). There were no complications.ln pts with long CTI (n=41). 22 patients were randomly assigned in the a-mm gp and 19 pts in the c
Journal of the American College of Cardiology, 2004
Journal of Cardiac Surgery, 2004
As less complex modifications of the Maze procedure have been developed, a number of energy sourc... more As less complex modifications of the Maze procedure have been developed, a number of energy sources have been introduced to facilitate the creation of electrically isolating lesions within the atria. These include cryoablation, radiofrequency, microwave, laser, and focused ultrasound. Although each of these sources works slightly differently, the goal of all thermal sources is to heat tissue to a temperature (50 • C) above which irreversible electrical isolation occurs. These sources have been utilized both endocardially in arrested heart procedures as well as epicardially in the beating heart setting. There are several obstacles to the use of these sources epicardially, mostly related to the heat sink effect of endocardial blood. Several recent modifications have been introduced that will hopefully increase the efficacy of these sources in beating heart applications.
Journal of Cardiac Surgery, 2004
In the last several years, a number of procedures have been conceived that have attempted to trea... more In the last several years, a number of procedures have been conceived that have attempted to treat atrial fibrillation (AF) by creating a limited set of lesions modeled after those of the Maze operation. These lesions have been created by a variety of means, including the traditional cut-and-sew method, but also by nonincisional techniques. These have included cryoablation as well as several thermal techniques, using radiofrequency, microwave, laser, and focused ultrasound energy. One reason for the development of these nonincisional techniques has been the desire to develop less invasive operations for the treatment of AF. The specific goal of our center has been to utilize these energy sources as well as other minimally invasive tools, such as surgical robots, to develop a closed chest, off-pump procedure for AF. The development of such a procedure is outlined in this article.
Journal of Cardiac Surgery, 2006
Background: The Maze III procedure is an effective surgical treatment for atrial fibrillation (AF... more Background: The Maze III procedure is an effective surgical treatment for atrial fibrillation (AF). However, it is not widely applied due to its complexity, increased operative times, and the risk of bleeding. Various energy sources have been introduced to simplify the traditional "cut and sew" approach. Methods: This study involves patients undergoing surgical atrial fibrillation ablation (SAFA) at a single institution from 1999 to 2005. Type of concomitant procedures, preoperative clinical characteristics, and chronicity of AF were evaluated in overall patient population. Parameters including surgical approach, lesion pattern, and energy source used were collected intraoperatively. Clinical outcomes examined were postoperative rhythm success, stroke, early mortality, and long-term survival. Results: Three hundred thirty-nine patients were identified. Three hundred twenty-eight (96.8%) patients had associated cardiac disease and underwent concomitant procedures; 75.8% of patients had persistent AF. Energy sources used were microwave (49.8%), radiofrequency (42.2%), and laser (8.0%). In 41.9% of cases a pulmonary vein encircling lesion was the only lesion created. Combination lesion sets were performed in the remaining cases. Rhythm success rates at 3, 6, 12, and 24 months were 74.1%, 68.2%, 74.5%, and 71.1%, respectively. Patients who underwent surgical removal of left atrial appendage by means of stapling or simple excision had no early postoperative stroke. Early mortality was 4.9%. Postoperative survival rates at 1, 3, and 5 years were 89.6%, 83.1%, and 78.0%. Conclusions: Surgical ablation of atrial fibrillation is a safe and effective procedure in restoring sinus rhythm with excellent postoperative survival rates. Further advancements in the field will eventually result in minimally invasive procedures with higher success rates.
Congestive Heart Failure, 2003
A wide array of surgical options are currently available for the treatment of congestive heart fa... more A wide array of surgical options are currently available for the treatment of congestive heart failure ranging from traditional coronary artery bypass grafting to total artificial heart implantation. The indications for each procedure depend on the severity of disease and the individual patients desires. Some surgical options are indicated for patients with moderate disease and prevent worsening heart failure, whereas other procedures are limited to patients who will only survive with high-risk surgery. Ongoing technologic advances are increasing the number of patients that benefit from the reparative surgical treatment of congestive heart failure.
The Annals of Thoracic Surgery, 2003
Background. Inhibition of angiotensin-converting enzyme (ACE) predisposes patients to vasodilator... more Background. Inhibition of angiotensin-converting enzyme (ACE) predisposes patients to vasodilatory hypotension after cardiopulmonary bypass (CPB). This hypotension has been correlated with arginine vasopressin deficiency and can be corrected by its replacement. In patients receiving ACE inhibition, we investigated whether initiation of vasopressin before CPB would diminish post-CPB hypotension and catecholamine use by avoiding vasopressin deficiency. Methods. Cardiac surgical patients on ACE inhibitor therapy were randomized to receive vasopressin (0.03 U/min) (n ؍ 13) or an equal volume of normal saline (n ؍ 14) starting 20 minutes before CPB. Results. Vasopressin did not change pre-CPB mean arterial pressure or pulmonary artery pressure. After CPB, the vasopressin group had a lower peak norepinephrine dose than the placebo group (4.6 ؎ 2.5 versus 7.3 ؎ 3.5 g/min, p ؍ 0.03), a shorter period on catecholamines (5 ؎ 6 versus 11 ؎ 7 hours, p ؍ 0.03), fewer hypotensive episodes (1 ؎ 1 versus 4 ؎ 2, p < 0.01), and a shorter intensive care unit length of stay (1.2 ؎ 0.4 versus 2.1 ؎ 1.4 days, p ؍ 0.03). Conclusions. In this cohort, prophylactic administration of vasopressin, at a dose without a vasopressor effect pre-CPB, reduced post-CPB hypotension and vasoconstrictor requirements, and was associated with a shorter intensive care unit stay.
The Annals of Thoracic Surgery, 2004
Background. Minimally invasive cardiac surgery has emerged as an alternative to conventional, ope... more Background. Minimally invasive cardiac surgery has emerged as an alternative to conventional, open surgery. Although most studies of robotically assisted cardiac surgery have reported morbidity and mortality, few have addressed outcome measures, such as pain and quality of life, which was the aim of this study. Methods. Eleven patients with atrial septal defects (ASD), and five patients with patent foramen ovale, underwent repair using the Da Vinci system (Intuitive Surgical, Mountain View, CA). The Medical Outcomes Study Short Form Survey (SF-36), along with two additional questions, were administered to these patients on postoperative day 30, along with a similar number of patients who underwent ASD repair by minithoracotomy or sternotomy. Quality of life endpoints included bodily pain, vitality, mental health, general health, physical function, and social function. Results. Robotic patients demonstrated significantly higher scores in 6 of the eight variables (p < 0.05). There was no significant difference in intensive care unit or overall hospital stay among the groups (p ؍ NS). Robotic patients returned to work after 40.2 ؎ 30.2 days, minithoracotomy patients after 45.6 ؎ 27.9 days, and sternotomy patients after 51.7 ؎ 40.2 days (p ؍ 0.767). There were no significant differences in SF-36 scores between patients who underwent mini-thoracotomy and sternotomy approaches. Conclusions. Closure of an ASD can be performed safely and effectively via an endoscopic approach. Robotic technology minimized the degree of invasiveness, hastened postoperative recovery, and improved quality of life, although length of hospital stay was unchanged.
The Annals of Thoracic Surgery, 2004
Background. The edge-to-edge mitral valve repair, first described by Alfieri in 1995 treats mitra... more Background. The edge-to-edge mitral valve repair, first described by Alfieri in 1995 treats mitral regurgitation when standard reparative techniques are difficult, unlikely to succeed, or have failed. This study examines one institution's medium-term experience with this procedure. Methods. This study involved patients undergoing edge-to-edge mitral valve repair at a single institution from 1997 to 2003. Preoperative and postoperative echocardiograms were compared. Postoperative morbidity was examined including need for reoperation and longterm medical management. Thirty-day survival and longterm actuarial survival were also determined. Results. Seventy-one patients comprised this study. Mitral regurgitation on echocardiogram went from 3.43 ؎ 0.86 to 0.39 ؎ 0.61 (p < 0.001) following repair. Thirty-day mortality was 3 of 71 (4.2%) patients. Actuarial survivals at 24 and 60 months were 84.5% and 58.3%, respectively; adjusted excluding noncardiac death they were 89.5% and 82.3%, respectively. Forty (56.3%) patients had concomitant ring placement and experienced similar survival to those repaired with the bow-tie stitch alone. Home telephone follow-up was conducted, and current medical therapy was determined on 51 patients; 59% were on a -blocker, 31% were on an angiotensinconverting enzyme (ACE) inhibitor, 27% were on a diuretic, and 22% were on digoxin. All were New York Heart Association (NYHA) class I or II. Three patients (4.2%) underwent mitral valve reoperation after a mean of 299 ؎ 429 days. In no case did the bow-tie suture rupture. Conclusions. Edge-to-edge mitral valve repair is a valuable tool in the armamentarium available to treat complex cases of mitral insufficiency or as an adjunct to standard repair techniques that fail to achieve an acceptable result.