Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Vaikom S. Mahadevan is active.

Publication


Featured researches published by Vaikom S. Mahadevan.


European Respiratory Review | 2012

Pulmonary arterial hypertension associated with congenital heart disease

Michele D'Alto; Vaikom S. Mahadevan

Pulmonary arterial hypertension (PAH) is a common complication of congenital heart disease (CHD), with most cases occurring in patients with congenital cardiac shunts. In patients with an uncorrected left-to-right shunt, increased pulmonary pressure leads to vascular remodelling and dysfunction, resulting in a progressive rise in pulmonary vascular resistance and increased pressures in the right heart. Eventually, reversal of the shunt may arise, with the development of Eisenmengers syndrome, the most advanced form of PAH-CHD. The prevalence of PAH-CHD has fallen in developed countries over recent years and the number of patients surviving into adulthood has increased markedly. Today, the majority of PAH-CHD patients seen in clinical practice are adults, and many of these individuals have complex disease or received a late diagnosis of their defect. While there have been advances in the management and therapy in recent years, PAH-CHD is a heterogeneous condition and some subgroups, such as those with Downs syndrome, present particular challenges. This article gives an overview of the demographics, pathophysiology and treatment of PAH-CHD and focuses on individuals with Downs syndrome as an important and challenging patient group.


Circulation | 2013

First in Human Transapical Implantation of an Inverted Transcatheter Aortic Valve Prosthesis to Treat Native Mitral Valve Stenosis

Ragheb Hasan; Vaikom S. Mahadevan; Heiko Schneider; Bernard Clarke

Transcatheter aortic valve implantation has become well established in the past decade. Its superiority in comparison with conventional surgical aortic valve replacements in high-risk patients has been demonstrated in the Partner Cohort B trial.1 We report the first case of using an inverted transcatheter Edwards Sapien valve (Edwards Lifesciences, CA) in the native mitral valve position, to treat severe calcific mitral stenosis. A 70-year-old woman was admitted to the intensive care unit after having had a cardiorespiratory collapse requiring ventilatory support. She was initially referred for assessment of worsening breathlessness, 7 years after coronary artery bypass grafting and aortic valve replacement with a 21-mm Top Hat (Sulzer, Carbomedics, Austin, TX) valve. Investigations in another center revealed patent grafts, severe calcific mitral stenosis with a valve area of 0.9 cm2 and a mean gradient …


Catheterization and Cardiovascular Interventions | 2013

Standalone balloon aortic valvuloplasty: Indications and outcomes from the UK in the transcatheter valve era

Muhammed Z. Khawaja; Manav Sohal; Haseeb Valli; Rafal Dworakowski; Stephen J. Pettit; David Roy; James D. Newton; Heiko Schneider; Ganesh Manoharan; Sagar N. Doshi; Douglas Muir; David H. Roberts; James Nolan; Mark Gunning; Cameron G. Densem; Mark S. Spence; Saqib Chowdhary; Vaikom S. Mahadevan; Stephen Brecker; Philip MacCarthy; Michael Mullen; Rodney H. Stables; Bernard Prendergast; Adam de Belder; Martyn Thomas; Simon Redwood; David Hildick-Smith

We sought to characterize UK‐wide balloon aortic valvuloplasty (BAV) experience in the TAVI era.


Catheterization and Cardiovascular Interventions | 2006

Aortic rupture following a covered stent for coarctation: Delayed recognition

Nicholas Collins; Vaikom S. Mahadevan; Eric Horlick

Primary stenting for aortic coarctation is frequently used in adult patients. Aortic rupture remains an infrequent complication. A number of strategies, including the use of covered stents, have been proposed to reduce the risk of this catastrophic complication. We describe a 51‐year‐old female who underwent stenting of aortic coarctation using a covered stent, which was complicated by aortic rupture. Treatment consisted of placement of an additional covered stent to seal the site of aortic disruption. The prevention and management of aortic rupture complicating aortic coarctation stenting are discussed.


Catheterization and Cardiovascular Interventions | 2006

Endovascular aortic coarctation stenting in adolescents and adults: Angiographic and hemodynamic outcomes

Vaikom S. Mahadevan; Isabelle F. Vondermuhll; Michael Mullen

Objectives: To assess the procedural, clinical, angiographic, and hemodynamic outcomes, including ambulatory blood pressure monitoring at 1 year in adolescent and adult patients undergoing primary stenting for treatment of aortic coarctation. Background: Stenting is widely used for treatment of aortic coarctation. Data regarding efficacy of this treatment for control of hypertension at 1 year is scant, with only one reported series of planned angiographic follow up. The impact of newer type stents for this procedure is also unknown. Methods: Thirty‐seven patients undergoing stenting for aortic coarctation, over a 3‐year period in a tertiary centre were studied as part of an observational protocol. Results: Peak gradient across the coarctation fell from 28.3 ± 15.1 to 3.7 ± 4.1 post procedure and was 11.9 ± 8.9 mmHg (P < 0.05 compared to baseline) at 1 year. There was one major complication (2.7%), with no deaths. Small aneurysms were seen in three patients (13%) on follow up angiography at 1 year. Right arm systolic blood pressures fell from 155 ± 19 to 132 ± 22 (P < 0.05) at 6 weeks and was 132 ± 16 mmHg (P < 0.05 compared to baseline) at 1 year. Ambulatory average systolic blood pressures fell from 142 ± 14 to 133 ± 15 at 6 weeks (P < 0.05) and to 125 ± 12 mmHg (P < 0.05 compared to baseline) at 1 year. No significant differences were seen in procedural outcomes between patients receiving Palmaz™ and CPNumed™ stents. Conclusion: Primary stenting of aortic coarctation in adolescents and adults results in excellent clinical and angiographic outcomes and sustained hemodynamic benefits at 1 year as evidenced by significant reduction in systolic blood pressure and gradients. Close follow up is required to monitor aneurysm formation.


Heart | 2007

Effect of endovascular stenting of aortic coarctation on biventricular function in adults

Yat-Yin Lam; Mehmet Gungor Kaya; Wei Li; Vaikom S. Mahadevan; Arif Anis Khan; Michael Y. Henein; Michael Mullen

Objective: To investigate the effect of endovascular stenting of aortic coarctation on biventricular function in adults during intermediate-term follow-up. Methods: 21 patients (age 34 (10) years) were studied prospectively before and 14 (2) months after coarctation stenting from year 2002 to 2005. Biventricular function and blood pressure measurements were made. The post-stenting results were compared with pre-stenting values (group 1), with 22 age- and sex-matched post-surgical repair patients (group 2) and 30 normal controls (group 3). Results: The peak systolic gradient across the coarctation site fell (55 (15) mm Hg to 18 (8) mm Hg, p<0.001). Systolic, mean blood pressure and left ventricular (LV) mass dropped after stenting (p<0.05 for all). LV long-axis function improved at intermediate-term follow-up (tissue Doppler imaging lateral and septal systolic and diastolic velocities and E/Em ratios: LSm, 6.5 (1.4) cm/s to 7.9 (1.7) cm/s; SSm, 5.8 (1.2) cm/s to 7.3 (1.6) cm/s; LEm, 8.1 (1.3) to 9.4 (2.3) cm/s; SEm, 6.7 (1.5) cm/s to 7.8 (1.9) cm/s; LE/Em, 11.2 (2.7) to 9.8 (2.8); SE/Em, 14.8 (5.3) to 11.8 (3.9); p<0.05 for all). No significant difference in LV ejection fraction, conventional LV diastolic measurements (E, A, E/A ratio, IVRT and DT) was found after stenting. No significant deterioration of right ventricular function was seen in stented patients. Both post-stenting and post-surgical repair patients had poorer LV long-axis function than controls (p<0.01 for all). Conclusions: Endovascular stenting of aortic coarctation resulted in medium-term LV mass regression and long-axis function improvement that may provide insight into long-term outcome of the stented patients. The results support aortic stenting in patients with anatomically suitable defects, given the additional benefit of avoiding cardiopulmonary bypass. The clinical significance of subclinical myocardial dysfunction in patients with stented or repaired coarctation warrants further studies.


Journal of Interventional Cardiology | 2010

Aortic balloon valvuloplasty: is there still a role in high-risk patients in the era of percutaneous aortic valve replacement?

Tahir Hamid; Jonas Eichhöfer; Bernard Clarke; Vaikom S. Mahadevan

OBJECTIVES To assess procedural and clinical outcomes in adults with severe aortic stenosis (AS) undergoing percutaneous aortic balloon valvuloplasty (PABV), who are considered unsuitable on initial assessment for surgical aortic valve replacement or transcatheter aortic valve implantation (TAVI). BACKGROUND Surgical valve replacement provides better outcomes than conservative treatment for patients with severe symptomatic AS; however, patients with multiple comorbidities or hemodynamic instability carry a high operative risk. While TAVI offers an alternative to surgery, not all patients are suitable. This study looks at medium-term outcomes in a series of high-risk patients undergoing PABV. METHODS Pre- and postprocedure aortic valve gradients were measured by catheterization and echocardiography. Patients were assessed for symptomatic benefit and clinical outcomes. RESULTS Over 4 years, 42 patients underwent PABV. Mean clinical follow-up was 8 +/- 5.8 months and survival was 63%. Mean echocardiographic aortic valve gradient fell from 84.6 +/- 27 mmHg to 51.3 +/- 16 mmHg (p < 0.05). In 29% (12/42) patients, PABV was performed as a bridge to definitive AVR. Four had surgical AVR and six had TAVI. Two had successful noncardiac surgery. Four patients died in the periprocedural period and all were in cardiogenic shock. Patients were in New York Heart Association (NYHA) class IV decreased from 60% to 5% postprocedure (p < 0.05). CONCLUSION PABV is useful as a palliation or bridge to definitive therapy for treatment of patients with severe AS unsuitable for surgery. It is associated with good medium-term cardiac outcomes and enables some patients to receive definitive therapy.


Circulation | 2016

Percutaneous Device Closure of Paravalvular Leak: Combined Experience from the United Kingdom and Ireland

Patrick A. Calvert; David Northridge; Iqbal S. Malik; Leonard M. Shapiro; Peter Ludman; Shakeel A. Qureshi; Michael Mullen; Robert Henderson; Mark Turner; Martin Been; Kevin Walsh; Ivan P. Casserly; Lindsay Morrison; Nicola L. Walker; John Thomson; Mark S. Spence; Vaikom S. Mahadevan; Angela Hoye; Philip MacCarthy; Matthew J. Daniels; Paul Clift; William R. Davies; Philip D. Adamson; Gareth J. Morgan; Suneil Aggarwal; Yasmin Ismail; Julian Ormerod; Habib R. Khan; Sujay Subash Chandran; Joseph V. DeGiovanni

Background: Paravalvular leak (PVL) occurs in 5% to 17% of patients following surgical valve replacement. Percutaneous device closure represents an alternative to repeat surgery. Methods: All UK and Ireland centers undertaking percutaneous PVL closure submitted data to the UK PVL Registry. Data were analyzed for association with death and major adverse cardiovascular events (MACE) at follow-up. Results: Three hundred eight PVL closure procedures were attempted in 259 patients in 20 centers (2004–2015). Patient age was 67±13 years; 28% were female. The main indications for closure were heart failure (80%) and hemolysis (16%). Devices were successfully implanted in 91% of patients, via radial (7%), femoral arterial (52%), femoral venous (33%), and apical (7%) approaches. Nineteen percent of patients required repeat procedures. The target valve was mitral (44%), aortic (48%), both (2%), pulmonic (0.4%), or transcatheter aortic valve replacement (5%). Preprocedural leak was severe (61%), moderate (34%), or mild (5.7%) and was multiple in 37%. PVL improved postprocedure ( P <0.001) and was none (33.3%), mild (41.4%), moderate (18.6%), or severe (6.7%) at last follow-up. Mean New York Heart Association class improved from 2.7±0.8 preprocedure to 1.6±0.8 ( P <0.001) after a median follow-up of 110 (7–452) days. Hospital mortality was 2.9% (elective), 6.8% (in-hospital urgent), and 50% (emergency) ( P <0.001). MACE during follow-up included death (16%), valve surgery (6%), late device embolization (0.4%), and new hemolysis requiring transfusion (1.6%). Mitral PVL was associated with higher MACE (hazard ratio [HR], 1.83; P =0.011). Factors independently associated with death were the degree of persisting leak (HR, 2.87; P =0.037), New York Heart Association class (HR, 2.00; P =0.015) at follow-up and baseline creatinine (HR, 8.19; P =0.001). The only factor independently associated with MACE was the degree of persisting leak at follow-up (HR, 3.01; P =0.002). Conclusion: Percutaneous closure of PVL is an effective procedure that improves PVL severity and symptoms. Severity of persisting leak at follow-up is independently associated with both MACE and death. Percutaneous closure should be considered as an alternative to repeat surgery. # Clinical Perspectives {#article-title-21}Background: Paravalvular leak (PVL) occurs in 5% to 17% of patients following surgical valve replacement. Percutaneous device closure represents an alternative to repeat surgery. Methods: All UK and Ireland centers undertaking percutaneous PVL closure submitted data to the UK PVL Registry. Data were analyzed for association with death and major adverse cardiovascular events (MACE) at follow-up. Results: Three hundred eight PVL closure procedures were attempted in 259 patients in 20 centers (2004–2015). Patient age was 67±13 years; 28% were female. The main indications for closure were heart failure (80%) and hemolysis (16%). Devices were successfully implanted in 91% of patients, via radial (7%), femoral arterial (52%), femoral venous (33%), and apical (7%) approaches. Nineteen percent of patients required repeat procedures. The target valve was mitral (44%), aortic (48%), both (2%), pulmonic (0.4%), or transcatheter aortic valve replacement (5%). Preprocedural leak was severe (61%), moderate (34%), or mild (5.7%) and was multiple in 37%. PVL improved postprocedure (P<0.001) and was none (33.3%), mild (41.4%), moderate (18.6%), or severe (6.7%) at last follow-up. Mean New York Heart Association class improved from 2.7±0.8 preprocedure to 1.6±0.8 (P<0.001) after a median follow-up of 110 (7–452) days. Hospital mortality was 2.9% (elective), 6.8% (in-hospital urgent), and 50% (emergency) (P<0.001). MACE during follow-up included death (16%), valve surgery (6%), late device embolization (0.4%), and new hemolysis requiring transfusion (1.6%). Mitral PVL was associated with higher MACE (hazard ratio [HR], 1.83; P=0.011). Factors independently associated with death were the degree of persisting leak (HR, 2.87; P=0.037), New York Heart Association class (HR, 2.00; P=0.015) at follow-up and baseline creatinine (HR, 8.19; P=0.001). The only factor independently associated with MACE was the degree of persisting leak at follow-up (HR, 3.01; P=0.002). Conclusion: Percutaneous closure of PVL is an effective procedure that improves PVL severity and symptoms. Severity of persisting leak at follow-up is independently associated with both MACE and death. Percutaneous closure should be considered as an alternative to repeat surgery.


American Journal of Cardiology | 2011

Efficacy and Safety of Bosentan for Pulmonary Arterial Hypertension in Adults With Congenital Heart Disease

Oliver Monfredi; Linda Griffiths; Bernard Clarke; Vaikom S. Mahadevan

The dual endothelin receptor antagonist, bosentan, has been shown to be well tolerated and effective in improving pulmonary arterial hypertension (PAH) symptoms in patients with Eisenmenger syndrome but data from longer-term studies are lacking. The aim of this study was to retrospectively analyze the long-term efficacy and safety of bosentan in adults with PAH secondary to congenital heart disease (PAH-CHD). Prospectively collected data from adult patients with PAH-CHD (with and without Down syndrome) initiated on bosentan from October 2007 through June 2010 were analyzed. Parameters measured before bosentan initiation (62.5 mg 2 times/day for 4 weeks titrated to 125 mg 2 times/day) and at each follow-up (1 month and 3, 6, 9, 12, 18, and 24 months) included exercise capacity (6-minute walk distance [6MWD]), pretest oxygen saturation, liver enzymes, and hemoglobin. Data were analyzed from 39 patients with PAH-CHD (10 with Down syndrome) who had received ≥ 1 dose of bosentan (mean duration of therapy 2.1 ± 1.5 years). A significant (p < 0.0001) average improvement in 6MWD of 54 m over a 2-year period in patients with PAH-CHD without Down syndrome was observed. Men patients had a 6MWD of 33 m greater than women (p < 0.01). In all patients, oxygen saturation, liver enzymes, and hemoglobin levels remained stable. There were no discontinuations from bosentan owing to adverse events. In conclusion, patients with PAH-CHD without Down syndrome gain long-term symptomatic benefits in exercise capacity after bosentan treatment. Men seem to benefit more on bosentan treatment. Bosentan appears to be well tolerated in patients with PAH-CHD with or without Down syndrome.


International Journal of Cardiology | 2009

Transcatheter closure of atrial septal defects with multiple devices in adults: Procedural and clinical outcomes

Vaikom S. Mahadevan; Natalie Gomperts; Kim Haberer; Candice K. Silversides; Lee N. Benson; Peter R. McLaughlin; Eric Horlick

OBJECTIVE This study reports the procedural, short and medium term outcomes in patients receiving multiple implants for device closure of secundum atrial septal defects (ASD). DESIGN AND SETTING From the database of the Toronto Congenital Cardiac Centre, 36 consecutive patients (mean age 46+/-15 years; 23 females) received >1 implant for closure of an interatrial communication. Short term (mean 97+/-77 days) and medium term (mean 2.5+/-1.4 years) follow-up data were analyzed. Procedures were performed under intracardiac echo (ICE) and fluoroscopic guidance. RESULTS The Amplatzer Septal Occluder (ASO) was implanted in all except one. Thirty-one patients had 2, and 4 patients, 3 ASO devices. There were no major adverse events at implantation or on follow-up. Patients with >NYHA class I symptoms fell from 44% to 6% (p<0.05) at 3 months. Right ventricular (RV) systolic pressure fell from 39+/-7 to 32+/-4 mm Hg in the short term (p<0.05), and to 30+/-4 mm Hg in the medium term (p<0.05, compared to baseline) and RV diameters fell from 48+/-5 to 40+/-5 (p<0.05) in the short term and to 38+/-8 mm (p=ns) in the medium term. Small residual leaks were present in 22% at 3 months and 12% (p<0.05) at 1 year. CONCLUSION Multiple ASD device implants can be safely employed with excellent outcomes. Significant reductions in RV pressure and diameter occur in the short term with a continued trend to benefit.

Collaboration


Dive into the Vaikom S. Mahadevan's collaboration.

Top Co-Authors

Avatar

Bernard Clarke

Manchester Royal Infirmary

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Jaspal Dua

Manchester Royal Infirmary

View shared research outputs
Top Co-Authors

Avatar

Michael Mullen

University College London

View shared research outputs
Top Co-Authors

Avatar

Tahir Hamid

Manchester Royal Infirmary

View shared research outputs
Top Co-Authors

Avatar

Anushree Agarwal

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Elyse Foster

University of California

View shared research outputs
Top Co-Authors

Avatar

Ian Harris

University of California

View shared research outputs
Researchain Logo
Decentralizing Knowledge