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Naresh Trehan

Publications and source records attributed to Naresh Trehan.

47 records · Page 3Linked to original sources
PubMed1998

Evaluation of Right Ventricular Function During CABG: Transesophageal Echocardiographic Assessment of Hepatic Venous Flow Versus Conventional Right Ventricular Performance Indices.

The vulnerability of right ventricle (RV) to ischemic insult during cardiac surgery is being increasingly recognized. This study aims to evaluate right ventricular function by measuring hepatic venous flow (HVF) patterns using intraoperative transesophageal echocardiography (TEE), and to compare HVF with other conventional two-dimensional echocardiographic and hemodynamic indices of RV performance. Patients undergoing coronary artery bypass grafting (CABG) were studied intraoperatively using a multiplane dual frequency 5/3.7-MHz phased array transducer, a pulmonary artery catheter, and an arterial catheter. Peak velocities and time velocity integrals of HVF pattern were studied. Peak systolic-diastolic ratio (S/D) of biphasic HVF and reverse flow ratio (% reverse flow/forward flow = % RF/FF) were also examined. Two-dimensional echocardiographic measurements included: (1) transverse plane long-axis (LA) and short-axis (SA) planimetered areas expressed as ratios; LA maximum major and minor-axis shortening fractions; (2) tricuspid annular plane systolic excursion (TAPSE) ratio. All data were obtained after induction of anesthesia (stage 1), after sternotomy (stage 2), aftercardiopulmonary bypass (CPB) (stage 3), and after sternal closure (stage 4). Pre-CPB all 35 patients had biphasic HVF by Doppler. In 31 patients peak S/D ratio was >1. After CPB, there was significant reduction in systolic forward flow (S wave), along with an increase in late systolic reverse flow (V wave) and an increase in % RF/FF. At this stage TAPSE ratio decreased (pre CPB 0.33 +/- 0.12 vs post CPB 0.30 +/- 0.11). There was simultaneous decrease in 2-D long-axis LA (pre CPB 0.52 +/- 0.11 vs post CPB 0.31 +/- 0.01) and max major axis LA (pre CPB 0.38 +/- 0.06 vs post CPB 0.31 +/- 0.11). Max major axis LA correlated significantly with changes in right atrial pressure (P < 0.05). Tricuspid annular motion diminished significantly at sternal closure. Hepatic systolic forward flow and TAPSE ratio can be an indirect measure of RV systolic functions in correlation with maximum major axis LA changes. Evaluation of HVF provides unique insight into right ventricular dynamics. It is an easy, safe, and sensitive method for assessing RV functions intraoperatively.

Journal Article↗
PubMedDate not supplied

Surgical treatment of post infarction left ventricular aneurysms: our experience with double breasting and Dor's repair.

BACKGROUND: This is a retrospective study of left ventricle (LV) aneurysm repair done at the Escorts Heart Institute and Research Centre, New Delhi, since October 1988. Two methods of LV aneurysm repair are practiced: double breasting (DB) and Dor's repair. The method varies with location, size, and extent of aneurysm and quality of the fibrotic wall of the aneurysm. METHODS: Between October 1988 and May 2001, 129 patients underwent LV aneurysm repair using one of the two techniques; 78 patients had Dor's repair while 51 patients had DB repair. RESULTS: Overall mortality was 2.3% (three patients). One patient died in the DB group, and two patients died in the Dor's repair group. Mean preoperative ejection fraction (EF) after surgery in DB was 31% while in Dor's repair it was 29.2%. EF showed improvement after surgery to 48.5% in DB and 46.6% in Dor's repair. Decrease in end-diastolic volume (EDV) in DB was from 146 to 91.4 cm3/m2, and in Dor's repair it was from 156 cm3/m2 to 88.6 cm3/m2. Decrease in end-systolic volume was from 101 cm3/m2 to 60.2 cm3/m2 in DB and from 109 cm3/m2 to 64.5 cm3/m2 in Dor's group. All of these values showed statistically significant improvement. At six months postoperatively, 83 patients (74.1%) out of 112 patients who were preoperatively in New York Heart Association (NYHA) Functional Classes III and IV improved to class II while 7 patients (6.3%) improved to class I. CONCLUSION: In our experience Dor's repair is indicated for anteroseptal and apical isolated posterior aneurysm to restore LV volume and geometry while DB is indicated for apical, anterolateral, and lateral aneurysms where septal involvement is less. These two techniques have definite indications and advantages with good results.

Adult↗
PubMedDate not supplied

Predictors of early outcome after coronary artery surgery in patients with severe left ventricular dysfunction.

BACKGROUND: The surgical survival in patients with severe myocardial dysfunction is critically dependent on the selection of patients. The present study was undertaken to identify the prognostic factors in such patients. METHODS: We analyzed the data of 176 consecutive patients (161 men, 15 women), aged 29 to 88 years (mean 58.43), with a left ventricular ejection fraction (LVEF) < 30% who underwent isolated coronary artery bypass grafting. The LVEF ranged from 15% to 30% (mean 27.18%). Preoperatively, 33% had angina, 19.9% had recent myocardial infarction, and 21.6% had congestive heart failure. The mean number of grafts was 2.5/patient. The intra-aortic balloon was used prophylactically in 20.5% of patients and therapeutically in 4.0% of patients. RESULTS: The hospital mortality was 2.3%. The complications occurred as follows: perioperative myocardial infarction in two (1.1%), intractable ventricular arrhythmias in two (1.1%), prolonged ventilation in four (2.3%) and peritoneal dialysis in 1 (0.6%). The mean ICU and hospital stay were 2.46 +/- 0.76 and 7.57 +/- 2.24 days, respectively. The predictors of survival on univariate analysis were New York Heart Association (NYHA) class (x2 = 14.458, p < 0.001), recent myocardial infarction (x2 = 5.852, p = 0.016), congestive heart failure (CHF) (x2 = 5.526, p = 0.019), and left ventricular end-systolic volume index (LVESVI) (x2 = 25.833, p < 0.001). However, on multivariate analysis, left ventricular end-systolic volume index was the only independent left ventricular function measurement predictive of survival (x2 = 10.228, p = 0.001). CONCLUSION: Left ventricular end-systolic volume index is the most important predictor of survival after coronary artery bypass surgery in patients with severe myocardial dysfunction.

Adult↗
PubMedDate not supplied

Beating heart versus conventional reoperative coronary artery bypass surgery.

BACKGROUND: The incidence of reoperative coronary artery bypass grafting is increasing with an increase in the number of patients undergoing coronary artery bypass surgery. The clinical outcome of redo coronary artery bypass grafting without cardiopulmonary bypass and conventional coronary artery bypass grafting using cardiopulmonary bypass are different. METHODS AND RESULTS: We compared clinical parameters in patients who underwent off-pump (n=156) versus on-pump (n=194) redo coronary artery bypass grafting performed between January 1995 and December 2001 in our institute, to determine if off-pump surgery has improved the surgical outcome of redo coronary artery bypass grafting and emerged as an ideal technique. Patients who underwent on-pump redo surgery required more postoperative blood transfusion (86.53% on-pump v. 12.82% off-pump. p=0.001), prolonged ventilatory support (>24 hours) (16.49% on-pump v. 7.7% off-pump, p=0.021) and higher inotropic support (23.71% on-pump v. 10.89% off-pump, p=0.003). On-pump redo coronary artery bypass grafting was also associated with a prolonged stay in the intensive care unit (40+/-6.2 hours on-pump v. 20+/-4.1 hours off-pump, p=0.001) and longer hospital stay (9+/-4.2 days on-pump v. 5+/-3.4 days off-pump, p=0.001). In-hospital mortality was higher in on-pump patients than in off-pump ones (7.7% v. 3.2%); however, this was not statistically significant (p=0.114). CONCLUSIONS: Off-pump redo coronary artery bypass grafting is a safe method of myocardial revascularization with lower operative morbidity and mortality, less requirement of blood products and early hospital discharge, compared with conventional on-pump redo coronary artery bypass grafting.

Aged↗
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Minimally invasive mitral valve surgery.

BACKGROUND: To reduce surgical trauma and the drawbacks associated with sternotomy, we performed robotically controlled, video-assisted mitral valve surgery, using either the port-access or the transthoracic clamp technique. METHODS AND RESULTS: Between September 1997 and September 2000, 221 patients (78 males, 143 females) underwent mitral valve surgery through a small right minithoracotomy using the port-access endovascular cardiopulmonary bypass system. Mitral valve exposure was facilitated with an endoscope attached to a voice-controlled robotic arm (AESOP 3000) allowing stabilization and voice-activated camera positioning. Twenty-six patients underwent mitral valve repair and 195 had valve replacement. In 197 patients, mitral valve surgery was the primary operation, while 24 were redo cases. Skin-to-skin mean operating time was 3.5 +/- 1.2 hours and aortic cross-clamp time was 58 +/- 16 min, mean intensive care unit stay was 22 +/- 7 hours and hospital stay 6.4 +/- 1.2 days. There was no re-exploration for bleeding. There was no late death or re-operation on mean follow-up of 16.4 +/- 12.2 months. Patients showed improvement in their NYHA functional class from 2.6 +/- 0.5 to 1.4 +/- 0.8 postoperatively. Outcomes were compared with those of our previous 220 patients who underwent mitral valve surgery with the median sternotomy approach. CONCLUSIONS: The use of video and robotic assistance in port-access mitral valve surgery not only minimizes the length of the incision, but also gives full visualization of the entire mitral valve apparatus. This approach provides comparable results with the sternotomy approach, as well as marked advantages of reduced intensive care unit stay. ,ower blood transfusion requirement, better cosmesis and earlier hospital discharge.

Adult↗
PubMedDate not supplied

Coronary calcium and coronary artery disease: an Indian perspective.

BACKGROUND: Coronary artery calcification is a part of the development of atherosclerosis. It occurs exclusively in atherosclerotic arteries and can be used as a noninvasive marker of coronary atherosclerosis. As there is no large-scale study on coronary calcium score reported in the Indian population till date, this study was undertaken for calculating the score in Indians at intermediate-to-high risk of coronary artery disease, and to correlate it with angiographically proven coronary artery disease. METHODS AND RESULTS: A total of 388 consecutive patients who underwent coronary calcium scoring and coronary angiography were included in the study. Calcium scoring was performed based on a modification of the Agatston Score using a high-speed computed tomography scanner (GE CT/i scanner). Coronary calcium scores were correlated with the presence or absence of significant coronary artery disease (defined as > or = 70% stenosis of at least one major epicardial coronary artery) on angiography. Out of 388 patients who underwent coronary angiography, 298 were found to have significant coronary artery disease. Mean coronary calcium score was significantly higher in patients with angiographically proven coronary artery disease (226.7+/-65.2) as compared to those who had normal angiograms (20.29+/-56.7; p value<0.0001). All the 72 patients who had a score > 400 had an abnormal angiogram (sensitivity 23.1%, specificity 100%, positive predictive value 100%, and negative predictive value 24.1%). On the other hand, among the patients who had a score > 0, 298 were found to have abnormal angiograms, while 16 had normal angiograms (sensitivity 95.5%, specificity 78.9%, positive predictive value 94.9%, and negative predictive value 81.1%). CONCLUSIONS: Detection of coronary calcium score by a helical computed tomography scanner is a useful tool for predicting the presence of significant coronary artery disease in intermediate-to-high risk patients. An absolute score of 0 has a high negative predictive value for the presence of coronary artery disease, and may obviate the need to perform coronary angiogram in intermediate-risk patients. On the other extreme, score > 400 is highly predictive of the presence of coronary artery disease, and virtually confirms the presence of significant coronary artery disease in intermediate-to-high risk patients.

Age Distribution↗
PubMedDate not supplied

Post-operative outcome of ventricular reshaping by septal exclusion in patients with severe left ventricular dysfunction.

BACKGROUND: Post-myocardial infarction, anteroseptal dysfunction or akinesia is treated by septal reshaping to improve the surgical outcome in patients with severe left ventricular dysfunction. METHODS AND RESULTS: Between February 2003 to December 2003, 30 consecutive patients with previous anterior wall myocardial infarction and severe ventricular dysfunction underwent septal reshaping. All the dyskinetic and akinetic septal areas were excluded using an oval dacron patch which was sutured from the healthy septal area to the anterior wall, resulting in formation of a new apex. There were two mortalities in the group. After a mean follow-up of 4.2 +/- 1.6 months (1-7 months) it was seen that this procedure resulted in significant reduction of ventricular volume, increase in ejection fraction, an improvement in New York Heart Association class from 2.9 +/- 1.1 to 1.7 +/- 0.3, and a better apical geometry. CONCLUSIONS: In selected patients with left anterior descending artery occlusion resulting in anteroseptal dyskinesia or akinesia, septal exclusion technique provides good clinical and morphological results with significant improvement in left ventricular function.

Adult↗
PubMedDate not supplied

Real-time three-dimensional transthoracic echocardiography.

BACKGROUND: Complex anatomy of intra-cardiac structures requires spatial orientation of image in three dimensions for better understanding and enhanced image interpretation. We evaluated the feasibility and efficacy of the emerging 'real-time three-dimensional transthoracic echocardiography' technique for comprehensive assessment of cardiac anatomy, physiology, pathomorphology and pathophysiology in patients with structural heart disease. METHODS AND RESULTS: Patients with structural heart disease (n=152) were evaluated by conventional two-dimensional transthoracic echocardiography and real-time three-dimensional transthoracic echocardiography using standard protocol. Fifty-six cases were of rheumatic etiology with multi-valvular involvement (mitral stenosis: 32; mitral regurgitation: 29; tricuspid regurgitation: 8; aortic valve disease: 11) and 21 cases of non-rheumatic valvular heart disease. A total of 38 congenital heart disease patients were examined including 23 patients with atrial septal defect. Left ventricular function (n=20) and right ventricular function (n=10) were also assessed using dedicated software. CONCLUSIONS: Results of real-time three-dimensional transthoracic echocardiography mitral valve area assessment by planimetery are comparable to two-dimensional transthoracic echocardiography with additional information about surface anatomy of leaflets and the subvalvular apparatus in real time with clear demarcation of commissural fusion and scallops of leaflets. Enface view of atrial septal defect with direct visualization of shape, size and number of defects, tricuspid valve area by planimetery, right ventricular shape, objective assessment of ventricular volumes and regurgitation vena contracta area are the fields where three-dimensional transthoracic echocardiography was of additive value to conventional two-dimensional transthoracic echcardiography. This study proves clinical feasibility of real-time three-dimensional transthoracic echocardiography but requires further validation of quantitative observations.

Adolescent↗
PubMedDate not supplied

Port-access approach for cardiac surgical procedures: our experience in 776 patients.

BACKGROUND: Recent advances in minimally invasive technology has expanded the application of the right thoracotomy approach for mitral valve surgery and atrial septal defect closure. The present study examines the feasibility, safety and efficacy of this technique. METHODS AND RESULTS: Between September 1997 and December 2004, 430 patients underwent mitral valve surgery through right anterolateral thoracotomy. The mitral valve was repaired in 62 patients, and 368 patients underwent mitral valve replacement. During same period, 336 patients underwent surgical closure of atrial septal defect. In all cases femoral artery and femoral venous cannulation was used for cardiopulmonary bypass. There was no approach-related limitation to surgical exposure, nor complication in cannulation of femoral vessels through the groin. Mean duration of cardiopulmonary bypass and cross-clamp time was 90 +/- 48 min and 51 +/- 29 min, respectively. Mean intubation time was 14.8 hours (range: 8-28 hours). Mean duration of intensive care andhospital stay was 26 hours (range: 18-38 hours) and 7 days (range: 5-17 days), respectively. In the atrial septal defect group, the mean cardiopulmonary bypass time and aortic cross-clamp time was 29 +/- 14 min and 19 +/- 8 min, respectively. Mean intensive care unit stay and mean hospital stay was 9.8 +/- 2.6 hours and 4.0 +/- 1.9 days, respectively. Hospital mortality was 0.46% (2/430) in the mitral valve group while there was no hospital mortality in atrial septal defect group. At a mean follow-up of 38.0 +/- 6.2 months there was one late death and two re-operations in the patients who underwent mitral valve surgery. CONCLUSIONS: Port-access approach is safe, offers faster recovery, cosmetic advantage, more patient satisfaction: it obviates the complications due to re-entry in redo cases and offers same efficacy as conventional operation. Furthermore, it is an excellent approach for mitral valve surgery in patients who had previous cardiac procedures. It has become our standard approach for repair of atrial septal defect and isolated mitral valve procedures.

Adolescent↗
PubMedDate not supplied

Isolated thrombus-producing right ventricular outflow tract obstruction: an unusual presentation of primary antiphospholipid antibody syndrome.

Right ventricular outflow tract obstruction secondary to an isolated organized thrombus is a rare entity. Proper diagnosis of this condition is essential for the survival of such patients. We describe the case of a middle aged woman who presented with dyspnea and decreased effort tolerance, and was managed with surgical excision of a firm mass which was identified as organized thrombus.

Adult↗