Review of current status of cardiovascular and thoracic surgery in Nepal: An analysis from collection of institutional database.

OBJECTIVE: Data collected from various institutions around the country was analyzed to assess the current status of cardiovascular and thoracic surgery in the country. METHODS: We collected data from institutions performing cardiovascular and thoracic surgery from all over the country through direct correspondence for the year 2019. Individual institution data on the number of surgeries performed for cardiac, vascular, and thoracic surgery and its outcome in terms of mortality were compiled. The data were further evaluated depending on the type of procedures performed. RESULTS: Overall, a total of 2264 cardiac surgeries were performed in the country in the year 2019. The majority of the surgeries were for valvular heart surgery accounting for 34.3%, followed by congenital surgeries (32.8%) and surgeries for coronary artery disease (25.9%). A total of 649 thoracic surgeries were documented, which is probably marginally less than the actual numbers because we were unable to include an additional few institutions performing low-volume or isolated thoracic procedures in this report. A total of 852 vascular procedures were performed in the country, which is probably underreported. The mortality rates for complex congenital procedures were higher than those reported in the literature and that of adult procedures such as valvular heart disease and coronary artery disease similar to literature. CONCLUSION: We evaluated the recent status of cardiovascular and thoracic surgery in the country with respect to the type of procedures and the postoperative outcomes.

Primary surgical repair of coarctation of the aorta in adolescents and adults: intermediate results and consequences of hypertension.

OBJECTIVES: Coarctation of the aorta is known to present with hypertension in older patients; we reviewed our experience and assessed the outcome of hypertension following surgical correction. METHODS: From April 2004 to date, 43 patients above the age of 12 underwent coarctation of the aorta repair. The mean age was 20.4 + 9.7 years (maximum 56 years); 21 (48.8%) were older than 18 years and 28 (65.1%) were men. Thirty (69.8%) patients had hypertension. Fourteen (32.6%) had a bicuspid aortic valve; 11 (25.6%) had patent ductus arteriosus; 6 (14%) had myxomatous mitral valve; 4 (9.3%) had ascending aortic aneurysms; and 2 (4.7%) had descending aneurysms. RESULTS: Surgical correction included resection and interposition of a tube graft in 31 (72.1%), an end-to-end anastomosis in 6 (14%) and patch aortoplasty in 3 (7%). Three (7%) patients required an extra-anatomical bypass: 1 had a long segment coarctation of the aorta, and 2 had a Bentall procedure with an ascending-to-descending aortic bypass. Staged procedures were done for concomitant disease in 4 (9.3%). There was 1 death: a 56-year-old woman died of refractory ventricular fibrillation during surgery. Thirty (69.8%) patients were discharged with antihypertensive medication. At a follow-up of 2.8 ± 2.2 years (maximum 9.2 years), the number of hypertensive patients decreased (17/36; 47.2%) (P = 0.042). Univariable predictors for persistence of hypertension revealed the use of an interpositional tube graft for repair (odds ratio 13.855, confidence interval 0.000-0.001; P = 0.001) as an indicator, whereas there were no independent predictors for persistence of hypertension. CONCLUSIONS: Surgical intervention is warranted irrespective of age and helps correct and control hypertension better; however, significant numbers of patients still require antihypertensive medication and regular monitoring. Intervention using an interposition tube graft may affect the prevalence of hypertension.

Anterior Pericardiectomy for Postinfective Constrictive Pericarditis: Intermediate-Term Outcomes.

BACKGROUND: Posttubercular constrictive pericarditis is prevalent pericardial disease in developing countries. Pericardiectomy is the treatment of choice but considered a procedure of high morbidity and mortality. METHODS: From January 2003 to December 2013 we performed 130 pericardiectomies. The patients' mean age was 22.95 ± 12.55 years, and there were 92 (71%) male patients. All patients were symptomatic; 118 (91%) were in New York Heart Association functional class III or IV. Almost all patients were diagnosed to be of tubercular origin: 14 (11%) were histopathologically proven, 77 (59%) had definitive history, 39 (30%) were suspected to be of tubercular origin, and 91 (70%) received prior antitubercular treatment. RESULTS: Anterior pericardiectomy was done without the use but with provision for cardiopulmonary bypass, which was required in 5 (3.8%) patients for repair of tear in right atrium. Following pericardiectomy central venous pressure dropped from 20.9 to 10.8 mm Hg. Early mortality was 10 (7.69%). Prolonged ventilation was required in 22 (16.92%) patients, 31 (23.84%) developed renal dysfunction, and there were 3 (3.12%) cases of new-onset atrial fibrillation. On analysis of univariate predictors for early mortality, low ejection fraction (p < 0.001) and preoperative atrial fibrillation (p < 0.001) were found to be significant. In a follow-up of 12 months, 85% patients were in New York Heart Association functional class I or II with mean ejection fraction of 52%. There was no recurrence of constriction from residual pericardium on 1-year follow-up. CONCLUSIONS: Anterior pericardiectomy is sufficient in patients with constrictive pericarditis of infective etiology. Preoperative low ejection fraction, atrial fibrillation, poor functional class, and constrictive effusive pericarditis results in poor surgical outcome.

The decellularized porcine heart valve matrix in tissue engineering: platelet adhesion and activation.

An approach in tissue engineering of heart valves is the use of decellularized xenogeneic matrices to avoid immune response after implantation. The decellularization process must preserve the structural components of the extracellular matrix to provide a biomechanically stable scaffold. However, it is known that in vascular lesions platelet adhesion to extracellular matrix components occurs and platelet activation is induced. In the present study we examined the effects of a decellularized porcine heart valve matrix on thrombocyte activation and the influence of re-endothelialisation in vitro. Porcine pulmonary conduits were decellularized using Triton X-100, Na-deoxycholate and Igepal CA-630 followed by a ribonuclease digestion. Cryostat sections of decellularized heart valves with and without seeding with human umbilical vein endothelial cells (HUVEC) were incubated with platelet rich plasma. Samples were either stained with fluorescent antibodies for CD41 and PAC-I (recognizing the activated fibrinogen receptor) or fixed with glutaraldehyde. Thereafter, the samples were processed for laser scanning microscopy (LSM) or scanning electron microscopy (SEM). Examination by LSM showed numerous platelets with co-localized staining for CD41 and PAC-1 on the nonseeded decellularized heart valve matrix whereas after seeding with endothelial cells no platelet activation was detected. SEM revealed platelet adhesion and aggregate formation only on the surface of the non-seeded or partially denuded matrix specimens. We show in this study that the decellularized porcine matrix acts as a platelet-activating surface. Seeding with endothelial cells effectively abolishes the platelet adhesion and activation and therefore is necessary to eliminate thrombogenicity in tissue engineered heart valves.