Sachin Khambadkone | University College London (original) (raw)

Papers by Sachin Khambadkone

Abstracts, 2019

Background Survival with critical aortic valve stenosis (CAS) can be successfully achieved in the... more Background Survival with critical aortic valve stenosis (CAS) can be successfully achieved in the short term. Long-term outcome however remains uncertain. We sought to study the long-term survival and reinterventions; exercise capacity and myocardial performance in a subgroup of long-term survivors. Methods Retrospective over 40 years of all patients (n=96) requiring intervention for CAS. A subgroup (n=25) of long-term survivors underwent cardiopulmonary exercise test, echocardiography and magnetic resonance imaging. Results Mean age at first intervention was 9±7.5 days. Early death occurred in 19 (19.8%) and overall reported death was 29 (32.9%). At 20 years, survival rate was 65.8% and freedom from reintervention was 24% (figure 1A and 1B).Abstract 86 Figure 1 A) Kaplan Meyer curve of survival. B) Kaplan Meyer of freedom from reintervention Median age of our long-term survivors, median age was 15.7±6.4 years, 16(64%) had a Ross procedure and 3(12%) had a mechanical aortic valve. Sixteen patients were in NYHA I, 3 NYHA II, 6 NYHA III. Overall peak VO2 was mildly depressed (84.6±24% predicted; 32.1±8.2 ml/kg/min), normal in 9(45%), severely depressed in 6 (30%). Mean left ventricle (LV) ejection fraction was 65.5±11.22% and mean LV end-diastolic volume Z score was 0.02±1.4. Mean LV outflow tract Vmax was 2.27±1.17 m/s. Four patients (16%) had moderate aortic regurgitation. Mean right ventricular outflow gradient was 19.23±23.57 mmHg. Five patients (20%) had severe LV diastolic dysfunction on echocardiography and confirmed by invasive measurement. Severe diastolic dysfunction was not associated with an older age (p=0.15), small ventricular dimension (p=0.2) or residual obstruction (p=0.39) but was associated with the presence of endocardial fibroelastosis (p=0.00014). Conclusions After an early mortality, long-term survival of patients with critical aortic stenosis is good at the expense of a high rate of reinterventions. Despite a good clinical status, myocardial assessment revealed a high rate of LV diastolic dysfunction that could be a marker of irreversible intrinsic myocardial damage.

Circulation, Oct 28, 2008

Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions, Jan 17, 2016

Percutaneous pulmonary valve implantation has gradually become the first line strategy for re-int... more Percutaneous pulmonary valve implantation has gradually become the first line strategy for re-intervention for right ventricular outflow tract dysfunction during long-term follow-up after congenital cardiac surgery in many centers. We describe a case of a patient with double outlet right ventricle (Fallot's type) with a doubly committed subarterial ventricular septal defect, where the unique anatomy precluded percutaneous pulmonary valve implantation. © 2016 Wiley Periodicals, Inc.

The Annals of Thoracic Surgery, Dec 1, 2010

Uhl&a... more Uhl's anomaly is a rare condition and surgical techniques are few and have had variable success. We present a novel and successful surgical technique to treat this difficult condition.

Radiology, Feb 1, 2007

To determine if magnetic resonance (MR) imaging data can be used to create rigid models that are ... more To determine if magnetic resonance (MR) imaging data can be used to create rigid models that are accurate representations of the right ventricular outflow tract (RVOT) and pulmonary trunk anatomy and if such models can be used to refine the selection of patients for percutaneous pulmonary valve implantation (PPVI). Institutional review board approval and informed patient consent were obtained. Twelve patients' MR data were analyzed and elaborated for input into a rapid prototyping (RP) system. RP models were successfully built and presented to two experienced cardiologists, who were retrospectively asked if they would have attempted PPVI. Their responses were compared with the documented decisions and outcomes of PPVI. For four subjects, both cardiologists correctly determined, on the basis of MR image or three-dimensional (3D) RP model findings, that PPVI should not have been attempted. Two patients in whom PPVI was attempted were considered to be unsuitable for the procedure after balloon sizing, and in another two patients, implantation was unsuccessful because of device instability. For the four patients in whom PPVI was suitable and the four in whom it was unsuitable, observers 1 and 2 correctly determined suitability for PPVI in four and two patients, respectively, by using the MR images alone. Both observers correctly determined the suitability of five patients by using the 3D models alone. Using 3D RP models resulted in more accurate selection of patients for PPVI than did using MR images.

In Circulation Lippincott Williams Wilkins, Nov 3, 2009

pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patie... more pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patients with right ventricular outflow tract dysfunction. Methods and Results-Between September 2000 and February 2007, 155 patients with stenosis and/or regurgitation underwent percutaneous pulmonary valve implantation. This led to significant reduction in right ventricular systolic pressure (from 63Ϯ18 to 45Ϯ13 mm Hg, PϽ0.001) and right ventricular outflow tract gradient (from 37Ϯ20 to 17Ϯ10 mm Hg, PϽ0.001). Follow-up ranged from 0 to 83.7 months (median 28.4 months). Freedom from reoperation was 93% (Ϯ2%), 86% (Ϯ3%), 84% (Ϯ4%), and 70% (Ϯ13%) at 10, 30, 50, and 70 months, respectively. Freedom from transcatheter reintervention was 95% (Ϯ2%), 87% (Ϯ3%), 73% (Ϯ6%), and 73% (Ϯ6%) at 10, 30, 50, and 70 months, respectively. Survival at 83 months was 96.9%. On time-dependent analysis, the first series of 50 patients (log-rank test PϽ0

Circulation, Oct 31, 2006

Circulation 112 U687 U688, Oct 25, 2005

Methods and Results— Patients with pulmonary regurgitation with or without stenosis after repair ... more Methods and Results— Patients with pulmonary regurgitation with or without stenosis after repair of congenital heart disease had percutaneous pulmonary valve implantation (PPVI). Mortality, hemodynamic improvement, freedom from explantation, and subjective and ...

In Circulation Lippincott Williams Wilkins, Oct 28, 2008

Scleredema adultorum is a rare connective tissue disorder reported usually following streptococca... more Scleredema adultorum is a rare connective tissue disorder reported usually following streptococcal infection, influenza, measles, and mumps. It has been reported occasionally following trauma and tuberculous lymphadenitis. This is a report of scleredema adultorum developing after chicken pox in an eight-year-old male child. The diagnosis was established by characteristic picture on skin biopsy using special stain. The patient had a benign course and a spontaneous recovery in two weeks. The case has been reported as the first case of scleredema adultorum developing after chicken pox.

EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology, Jan 8, 2015

We report the application of patient-specific computational models to plan the treatment of compl... more We report the application of patient-specific computational models to plan the treatment of complex aortic re-coarctation (rCoA) with a proximal aberrant right subclavian artery in a patient who had previously undergone bare metal stenting. Clinically acquired images were used to set up patient-specific computational models for finite element (FE) and fluid dynamics (CFD) analyses. The 3D geometry was reconstructed from computed tomography and echocardiography images. Computer-generated deployment of a CP covered stent (NuMED, Hopkinton, NY, USA) at different diameters was tested using FE simulations. CFD analyses based on preoperative magnetic resonance flow measurements allowed assessment of rCoA pressure relief and right subclavian artery perfusion in the different scenarios. The simulations suggested an expansion diameter for the CP stent (8 zigs, length=28 mm) of between 16 and 18 mm to relieve the obstruction, cover the aneurysm and maintain satisfactory flow to the right subc...

Pediatric Cardiology

In most newborns with left heart obstruction, the choice between a single-ventricle or biventricu... more In most newborns with left heart obstruction, the choice between a single-ventricle or biventricular management pathway is clear. However, in some neonates with a "borderline" left ventricle, this decision is difficult. Existing criteria do not reliably identify neonates who will have a good long-term outlook after biventricular repair (BVR). The objective of this study was prospective assessment of the outcome after BVR for newborns in whom the left ventricle (LV) was considered "borderline" by an expert group. This study was a prospective follow-up evaluation of neonates with obstructive left heart disease related to a "borderline" LV who underwent biventricular management between January 2005 and April 2011. Of 154 neonates who required intervention for left heart obstruction, 13 (7.8 %) met the echocardiographic (echo) inclusion criteria. At the first and last echo, the z-scores were respectively -1.76 ± 1.37 and -0.66 ± 1.47 (p = 0.013) for the mit...

Cardiology in the Young

We determined the relationship between aortic arch anatomy in tetralogy of Fallot with pulmonary ... more We determined the relationship between aortic arch anatomy in tetralogy of Fallot with pulmonary stenosis and chromosomal or genetic abnormality, by performing analysis of 257 consecutive patients undergoing surgical repair from January, 2003 to March, 2011. Chromosomal or genetic abnormality was identified in 49 of the 257 (19%) patients. These included trisomy 21 (n = 14); chromosome 22q11.2 deletion (n = 16); other chromosomal abnormalities (n = 9); CHARGE (n = 2); Pierre Robin (n = 2); and Kabuki, Alagille, Holt-Oram, Kaufman McKusick, Goldenhar, and PHACE (n = 1 each). Aortic anatomy was classified as left arch with normal branching, right arch with mirror image branching, left arch with aberrant right subclavian artery, or right arch with aberrant left subclavian artery. Associated syndromes occurred in 33 of 203 (16%) patients with left arch and normal branching (odds ratio 1); three of 36 (8%) patients with right arch and mirror image branching (odds ratio 0.4, 95% confidenc...

Pediatric Cardiology

Echocardiographic measurements of diastolic function have not been validated against invasive pre... more Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single-ventricle population. The authors hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with a single-ventricle physiology. The conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (τ), the maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness (μ). The echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and the TDI-derived isovolumic relaxation time (IVRT'). The correlation between PVL and echocardiographic measures was examined. The study enrolled 13 patients at various stages of surgical palliation. The...

Congenital Heart Disease

Background Differences in ventricular geometry and physiology of patients with single ventricle a... more Background Differences in ventricular geometry and physiology of patients with single ventricle anatomy complicate the application of traditional, noninvasive measurements of systolic function. We compared noninvasive measures of ventricular systolic function in single ventricle patients with invasive measures to evaluate their validity in this population.MethodsA secondary analysis of patients with single ventricle physiology enrolled in the multi-institutional research project, “multi-scale modeling of single ventricle hearts,” was performed. Pressure–volume loops (PVLs) were recorded using microconductance catheters. Transthoracic echocardiogram and cardiac magnetic resonance imaging were performed on the same day. PVL indices of systolic function including end-systolic elastance (Ees), maximal rate of pressure increase (dP/dTmax), and stroke work indexed to end-diastolic volume (SW/EDV) were compared with noninvasive measures, including echocardiographic myocardial performance i...

Hypoplastic left heart syndrome (HLHS) is a congenital heart disease whose staged surgical pallia... more Hypoplastic left heart syndrome (HLHS) is a congenital heart disease whose staged surgical palliation aims to progressively separate the systemic and pulmonary circulations. The first stage or Norwood procedure [1] involves surgical reconstruction of the aortic arch, usually with pulmonary homograft patch [2]. Recent evidence suggested that, because of this extensive reconstruction, HLHS patients have abnormal elastic properties [3] and reduced distensibility [4,5] of the ascending aorta. However, the impact of the reconstructed aorta and its abnormal elastic properties on ventricular mechanics, i.e. ventriculo-arterial coupling mismatch, has not been assessed. In the light of this mismatch, a change in impedance on the arterial side will reflect on the ventricular side and quantification of this phenomenon may provide mechano-energetic information for further understanding a complex physiology such as palliated HLHS with aortic arch surgical reconstruction. In this study we suggest...

Abstracts, 2019

Background Survival with critical aortic valve stenosis (CAS) can be successfully achieved in the... more Background Survival with critical aortic valve stenosis (CAS) can be successfully achieved in the short term. Long-term outcome however remains uncertain. We sought to study the long-term survival and reinterventions; exercise capacity and myocardial performance in a subgroup of long-term survivors. Methods Retrospective over 40 years of all patients (n=96) requiring intervention for CAS. A subgroup (n=25) of long-term survivors underwent cardiopulmonary exercise test, echocardiography and magnetic resonance imaging. Results Mean age at first intervention was 9±7.5 days. Early death occurred in 19 (19.8%) and overall reported death was 29 (32.9%). At 20 years, survival rate was 65.8% and freedom from reintervention was 24% (figure 1A and 1B).Abstract 86 Figure 1 A) Kaplan Meyer curve of survival. B) Kaplan Meyer of freedom from reintervention Median age of our long-term survivors, median age was 15.7±6.4 years, 16(64%) had a Ross procedure and 3(12%) had a mechanical aortic valve. Sixteen patients were in NYHA I, 3 NYHA II, 6 NYHA III. Overall peak VO2 was mildly depressed (84.6±24% predicted; 32.1±8.2 ml/kg/min), normal in 9(45%), severely depressed in 6 (30%). Mean left ventricle (LV) ejection fraction was 65.5±11.22% and mean LV end-diastolic volume Z score was 0.02±1.4. Mean LV outflow tract Vmax was 2.27±1.17 m/s. Four patients (16%) had moderate aortic regurgitation. Mean right ventricular outflow gradient was 19.23±23.57 mmHg. Five patients (20%) had severe LV diastolic dysfunction on echocardiography and confirmed by invasive measurement. Severe diastolic dysfunction was not associated with an older age (p=0.15), small ventricular dimension (p=0.2) or residual obstruction (p=0.39) but was associated with the presence of endocardial fibroelastosis (p=0.00014). Conclusions After an early mortality, long-term survival of patients with critical aortic stenosis is good at the expense of a high rate of reinterventions. Despite a good clinical status, myocardial assessment revealed a high rate of LV diastolic dysfunction that could be a marker of irreversible intrinsic myocardial damage.

Circulation, Oct 28, 2008

Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions, Jan 17, 2016

Percutaneous pulmonary valve implantation has gradually become the first line strategy for re-int... more Percutaneous pulmonary valve implantation has gradually become the first line strategy for re-intervention for right ventricular outflow tract dysfunction during long-term follow-up after congenital cardiac surgery in many centers. We describe a case of a patient with double outlet right ventricle (Fallot's type) with a doubly committed subarterial ventricular septal defect, where the unique anatomy precluded percutaneous pulmonary valve implantation. © 2016 Wiley Periodicals, Inc.

The Annals of Thoracic Surgery, Dec 1, 2010

Uhl&a... more Uhl's anomaly is a rare condition and surgical techniques are few and have had variable success. We present a novel and successful surgical technique to treat this difficult condition.

Radiology, Feb 1, 2007

To determine if magnetic resonance (MR) imaging data can be used to create rigid models that are ... more To determine if magnetic resonance (MR) imaging data can be used to create rigid models that are accurate representations of the right ventricular outflow tract (RVOT) and pulmonary trunk anatomy and if such models can be used to refine the selection of patients for percutaneous pulmonary valve implantation (PPVI). Institutional review board approval and informed patient consent were obtained. Twelve patients' MR data were analyzed and elaborated for input into a rapid prototyping (RP) system. RP models were successfully built and presented to two experienced cardiologists, who were retrospectively asked if they would have attempted PPVI. Their responses were compared with the documented decisions and outcomes of PPVI. For four subjects, both cardiologists correctly determined, on the basis of MR image or three-dimensional (3D) RP model findings, that PPVI should not have been attempted. Two patients in whom PPVI was attempted were considered to be unsuitable for the procedure after balloon sizing, and in another two patients, implantation was unsuccessful because of device instability. For the four patients in whom PPVI was suitable and the four in whom it was unsuitable, observers 1 and 2 correctly determined suitability for PPVI in four and two patients, respectively, by using the MR images alone. Both observers correctly determined the suitability of five patients by using the 3D models alone. Using 3D RP models resulted in more accurate selection of patients for PPVI than did using MR images.

In Circulation Lippincott Williams Wilkins, Nov 3, 2009

pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patie... more pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patients with right ventricular outflow tract dysfunction. Methods and Results-Between September 2000 and February 2007, 155 patients with stenosis and/or regurgitation underwent percutaneous pulmonary valve implantation. This led to significant reduction in right ventricular systolic pressure (from 63Ϯ18 to 45Ϯ13 mm Hg, PϽ0.001) and right ventricular outflow tract gradient (from 37Ϯ20 to 17Ϯ10 mm Hg, PϽ0.001). Follow-up ranged from 0 to 83.7 months (median 28.4 months). Freedom from reoperation was 93% (Ϯ2%), 86% (Ϯ3%), 84% (Ϯ4%), and 70% (Ϯ13%) at 10, 30, 50, and 70 months, respectively. Freedom from transcatheter reintervention was 95% (Ϯ2%), 87% (Ϯ3%), 73% (Ϯ6%), and 73% (Ϯ6%) at 10, 30, 50, and 70 months, respectively. Survival at 83 months was 96.9%. On time-dependent analysis, the first series of 50 patients (log-rank test PϽ0

Circulation, Oct 31, 2006

Circulation 112 U687 U688, Oct 25, 2005

Methods and Results— Patients with pulmonary regurgitation with or without stenosis after repair ... more Methods and Results— Patients with pulmonary regurgitation with or without stenosis after repair of congenital heart disease had percutaneous pulmonary valve implantation (PPVI). Mortality, hemodynamic improvement, freedom from explantation, and subjective and ...

In Circulation Lippincott Williams Wilkins, Oct 28, 2008

Scleredema adultorum is a rare connective tissue disorder reported usually following streptococca... more Scleredema adultorum is a rare connective tissue disorder reported usually following streptococcal infection, influenza, measles, and mumps. It has been reported occasionally following trauma and tuberculous lymphadenitis. This is a report of scleredema adultorum developing after chicken pox in an eight-year-old male child. The diagnosis was established by characteristic picture on skin biopsy using special stain. The patient had a benign course and a spontaneous recovery in two weeks. The case has been reported as the first case of scleredema adultorum developing after chicken pox.

EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology, Jan 8, 2015

We report the application of patient-specific computational models to plan the treatment of compl... more We report the application of patient-specific computational models to plan the treatment of complex aortic re-coarctation (rCoA) with a proximal aberrant right subclavian artery in a patient who had previously undergone bare metal stenting. Clinically acquired images were used to set up patient-specific computational models for finite element (FE) and fluid dynamics (CFD) analyses. The 3D geometry was reconstructed from computed tomography and echocardiography images. Computer-generated deployment of a CP covered stent (NuMED, Hopkinton, NY, USA) at different diameters was tested using FE simulations. CFD analyses based on preoperative magnetic resonance flow measurements allowed assessment of rCoA pressure relief and right subclavian artery perfusion in the different scenarios. The simulations suggested an expansion diameter for the CP stent (8 zigs, length=28 mm) of between 16 and 18 mm to relieve the obstruction, cover the aneurysm and maintain satisfactory flow to the right subc...

Pediatric Cardiology

In most newborns with left heart obstruction, the choice between a single-ventricle or biventricu... more In most newborns with left heart obstruction, the choice between a single-ventricle or biventricular management pathway is clear. However, in some neonates with a "borderline" left ventricle, this decision is difficult. Existing criteria do not reliably identify neonates who will have a good long-term outlook after biventricular repair (BVR). The objective of this study was prospective assessment of the outcome after BVR for newborns in whom the left ventricle (LV) was considered "borderline" by an expert group. This study was a prospective follow-up evaluation of neonates with obstructive left heart disease related to a "borderline" LV who underwent biventricular management between January 2005 and April 2011. Of 154 neonates who required intervention for left heart obstruction, 13 (7.8 %) met the echocardiographic (echo) inclusion criteria. At the first and last echo, the z-scores were respectively -1.76 ± 1.37 and -0.66 ± 1.47 (p = 0.013) for the mit...

Cardiology in the Young

We determined the relationship between aortic arch anatomy in tetralogy of Fallot with pulmonary ... more We determined the relationship between aortic arch anatomy in tetralogy of Fallot with pulmonary stenosis and chromosomal or genetic abnormality, by performing analysis of 257 consecutive patients undergoing surgical repair from January, 2003 to March, 2011. Chromosomal or genetic abnormality was identified in 49 of the 257 (19%) patients. These included trisomy 21 (n = 14); chromosome 22q11.2 deletion (n = 16); other chromosomal abnormalities (n = 9); CHARGE (n = 2); Pierre Robin (n = 2); and Kabuki, Alagille, Holt-Oram, Kaufman McKusick, Goldenhar, and PHACE (n = 1 each). Aortic anatomy was classified as left arch with normal branching, right arch with mirror image branching, left arch with aberrant right subclavian artery, or right arch with aberrant left subclavian artery. Associated syndromes occurred in 33 of 203 (16%) patients with left arch and normal branching (odds ratio 1); three of 36 (8%) patients with right arch and mirror image branching (odds ratio 0.4, 95% confidenc...

Pediatric Cardiology

Echocardiographic measurements of diastolic function have not been validated against invasive pre... more Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single-ventricle population. The authors hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with a single-ventricle physiology. The conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (τ), the maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness (μ). The echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and the TDI-derived isovolumic relaxation time (IVRT'). The correlation between PVL and echocardiographic measures was examined. The study enrolled 13 patients at various stages of surgical palliation. The...

Congenital Heart Disease

Background Differences in ventricular geometry and physiology of patients with single ventricle a... more Background Differences in ventricular geometry and physiology of patients with single ventricle anatomy complicate the application of traditional, noninvasive measurements of systolic function. We compared noninvasive measures of ventricular systolic function in single ventricle patients with invasive measures to evaluate their validity in this population.MethodsA secondary analysis of patients with single ventricle physiology enrolled in the multi-institutional research project, “multi-scale modeling of single ventricle hearts,” was performed. Pressure–volume loops (PVLs) were recorded using microconductance catheters. Transthoracic echocardiogram and cardiac magnetic resonance imaging were performed on the same day. PVL indices of systolic function including end-systolic elastance (Ees), maximal rate of pressure increase (dP/dTmax), and stroke work indexed to end-diastolic volume (SW/EDV) were compared with noninvasive measures, including echocardiographic myocardial performance i...

Hypoplastic left heart syndrome (HLHS) is a congenital heart disease whose staged surgical pallia... more Hypoplastic left heart syndrome (HLHS) is a congenital heart disease whose staged surgical palliation aims to progressively separate the systemic and pulmonary circulations. The first stage or Norwood procedure [1] involves surgical reconstruction of the aortic arch, usually with pulmonary homograft patch [2]. Recent evidence suggested that, because of this extensive reconstruction, HLHS patients have abnormal elastic properties [3] and reduced distensibility [4,5] of the ascending aorta. However, the impact of the reconstructed aorta and its abnormal elastic properties on ventricular mechanics, i.e. ventriculo-arterial coupling mismatch, has not been assessed. In the light of this mismatch, a change in impedance on the arterial side will reflect on the ventricular side and quantification of this phenomenon may provide mechano-energetic information for further understanding a complex physiology such as palliated HLHS with aortic arch surgical reconstruction. In this study we suggest...