Milind Hote

Prophylactic Vasopressin in Patients Receiving the Angiotensin-Converting Enzyme Inhibitor Ramipril Undergoing Coronary Artery Bypass Graft Surgery

OBJECTIVE The purpose of this study was to compare the effects of continuation versus discontinuation of the angiotensin-converting enzyme (ACE) inhibitor ramipril and assess the efficacy of prophylactic vasopressin infusion on hemodynamic stability and vasoactive drug requirements in patients undergoing coronary artery bypass graft (CABG) surgery. DESIGN A prospective, randomized, double-blinded, single-center clinical study. SETTING Tertiary care hospital. PARTICIPANTS Forty-seven patients on the ACE inhibitor ramipril for 6 weeks before undergoing elective primary CABG surgery on cardiopulmonary bypass (CPB). INTERVENTIONS Patients were randomly divided into 3 groups: group A (n = 16), patients discontinued ramipril 24 hours before surgery; group B (n = 16), patients continued ramipril until the morning of surgery; and group C (n = 15), patients continued ramipril until the morning of surgery and received vasopressin infusion (0.03 U/min) from the onset of rewarming until the hemodynamics were stable without vasopressor agents. The anesthetic technique and conduct of CPB were standardized for all the groups. Hemodynamic parameters and vasoactive drug requirements were recorded for 3 days postoperatively. MEASUREMENTS AND MAIN RESULTS Patients in group A maintained stable mean arterial pressure (MAP) and systemic vascular resistance (SVR). In group B, MAP and SVR decreased after the induction of anesthesia and remained so throughout surgery (p < 0.05). In group C, MAP and SVR decreased upon the induction of anesthesia (p < 0.05) but normalized after CPB. CONCLUSIONS Preoperative ACE inhibitor continuation predisposed to hypotension upon the induction of anesthesia and in the post-CPB period. Prophylactic low-dose vasopressin infusion prevented post-CPB hypotension. Low-dose vasopressin can be considered as potential therapy in these patients.

The Role of Oral Coenzyme Q10 in Patients Undergoing Coronary Artery Bypass Graft Surgery

OBJECTIVE Cardiopulmonary bypass (CPB) is known to induce oxidative stress. Because total antioxidant level is reduced during CPB, the supplementation of an antioxidant might help in attenuating the oxidative stress response. The authors sought to evaluate the efficacy of oral coenzyme Q10, in attenuating the oxidative stress to CPB and altering the clinical outcome in patients undergoing coronary artery bypass graft (CABG) surgery. DESIGN A prospective, randomized, single-center clinical study. SETTING A cardiothoracic center of a tertiary hospital. PARTICIPANTS Thirty patients scheduled for elective CABG surgery. INTERVENTIONS The study group (n = 15) received oral coenzyme Q10, 150 to 180 mg/d, for 7 to 10 days preoperatively, whereas the control group (n = 15) did not receive any antioxidant or placebo. The anesthesia technique was standardized in both groups. Blood samples for total antioxidant level, blood glucose level, and clinical outcome parameters up to 24 hours postoperatively were compared. MEASUREMENTS AND MAIN RESULTS There was no difference in the antioxidant level between the 2 groups at any point of time. However, in the study group, 24 hours after aortic clamp release, it was significantly higher than baseline (p < 0.05). The blood glucose was significantly lower in the study group at aortic clamp removal and 4 hours after clamp removal as compared with the control group (p = 0.01). The study group had significantly fewer reperfusion arrhythmias, lower total inotropic requirement, mediastinal drainage, blood product requirement, and shorter hospital stays compared with the control group. CONCLUSION Oral coenzyme Q10 therapy for 7 to 10 days preoperatively could improve clinical outcome in patients undergoing CABG surgery. A larger study group is recommended for confirmation.

Light and electron microscopic features of surgically excised left atrial appendage in rheumatic heart disease patients with atrial fibrillation and sinus rhythm

INTRODUCTION There are few studies comparing the pathology of the remodeled substrate in patients of rheumatic heart disease with atrial fibrillation (AF) and normal sinus rhythm (NSR). METHODS The study group comprised 30 patients with rheumatic heart disease undergoing mitral valve replacement. Excised left atrial appendages of these patients [17 with persistent AF and 13 NSR (control group)] were subjected to light and electron microscopic examination. RESULTS The histopathological findings of the myocardium were characterized by cardiomyocyte hypertrophy (CH), nuclear enlargement (NE), perinuclear clearing (PC), sarcoplasmic vacuolation (SV), fibrosis, and inflammation in the patients with AF and NSR. NE (17/17 vs. 4/13; P=.004), PC (17/17 vs. 4/13; P=.004), SV (17/17 vs. 9/13; P=.06), and fibrosis (15/17 vs. 3/13; P=.001) were all significantly more common in patients with AF. Inflammatory cells were observed in 9/17 patients of AF as compared to 1 in NSR patients (9/17 vs. 1/13; P=.02). CH was common in the patients with AF as compared with those in NSR (17/17 vs. 10/13; P=.103). In AF patients, electron microscopy revealed cardiomyocytes with depletion of the contractile elements (Z-bands), glycogen particle accumulation, and an increase in mitochondria. Cells severely affected by AF showed loss of contractile elements with extensive areas of SV, presence of myelin figures, and mitochondrial aggregates. Majority of AF cases showed extensive fibrosis in the form of collagen bundles in the interstitium. CONCLUSION The left atrial substrate in AF as compared with NSR, in rheumatic heart disease patients, is associated with significant degenerative remodeling and ongoing inflammation that is associated with extensive fibrosis.

Calcified amorphous tumor of the heart in an adult female: a case report

IntroductionCardiac calcified amorphous tumor is a rare, non-neoplastic intra-cavity cardiac mass composed of calcium deposits in a background of amorphous degenerating fibrinous material. Only a few cases of this rare lesion have been reported in the available literature. Clinico-pathological differentiation of this lesion from calcified atrial myxoma, calcified thrombi or other cardiac neoplasms is extremely difficult; hence pathologic examination is the mainstay of diagnosis. To the best of our knowledge this entity has not been reported in the Indian literature.Case presentationA 40-year-old woman of Indian origin presented with progressive dyspnea, fatigue and cough. She was diagnosed as having a calcified right atrial mass. The mass was excised. Histologic examination revealed the mass to be composed of amorphous eosinophilic fibrin with dense calcification. No myxomatous tissue was seen and a final diagnosis of calcified amorphous tumor of the heart was rendered.ConclusionsCalcified amorphous tumor is a rare cardiac lesion with an excellent outcome following complete surgical removal. Since clinico-radiologic differentiation from other cardiac masses is not possible in most cases, histopathological examination is the only modality for diagnosis. Hence, histopathologists should be aware of this rare entity in the differential diagnoses of cardiac mass.

Comparison of 48 h and 72 h of prophylactic antibiotic therapy in adult cardiac surgery: a randomized double blind controlled trial

OBJECTIVES To determine whether the duration of antibiotic prophylaxis influences the rate of surgical site infection in patients undergoing coronary bypass grafting or valve replacement. PATIENTS AND METHODS Adult patients undergoing elective coronary artery bypass grafting (CABG) and valve surgery were included in this randomized double blind study. Between April 2007 and April 2008, 235 patients were randomly assigned to one of two groups using random number table and sealed envelope technique. The groups received prophylactic antibiotic therapy for either 48 h (the 48 h group) or 72 h (the 72 h group). These patients were monitored for surgical site infection. RESULTS The mean age was 52.94 +/- 16.30 and 55.27 +/- 16.63 years, respectively, in the two groups. The incidence of co-morbid conditions as well as operative conditions was similar between the groups. During the study period 20 patients developed surgical site infections and 7 patients other infections. In modified treatment analysis, the infection rates were 7.6% (9 patients, n = 119) in the group receiving 48 h of prophylactic antibiotic therapy and 10.2% (11 patients, n = 108) in the group receiving 72 h of prophylactic antibiotic therapy, and the difference was statistically non-significant (P > 0.05). In the per protocol analysis the infection rates were 5% (5 patients, n = 100) in the group receiving 48 h of prophylactic antibiotic therapy and 8% (8 patients, n = 100) in the group receiving 72 h of prophylactic antibiotic therapy, and the difference was again statistically non-significant (P > 0.05). The results of Fishers exact test revealed that the duration of surgery lasting for >5 h is an independent risk factor for surgical site infection. CONCLUSIONS Forty-eight hours of a prophylactic antibiotic combination using a third-generation cephalosporin and an aminoglycoside is as effective as a 72 h regimen for preventing surgical site infection in patients undergoing CABG and valve surgery.

Beneficial effects of aqueous extract of stem bark of Terminalia arjuna (Roxb.), An ayurvedic drug in experimental pulmonary hypertension.

ETHNOPHARMACOLOGICAL RELEVANCE The stem bark of Terminalia arjuna (Roxb.) is widely used in Ayurveda in various cardiovascular diseases. Many animal and clinical studies have validated its anti-ischemic, antihypertensive, antihypertrophic and antioxidant effects. Pulmonary hypertension (PH) is a fatal disease which causes right ventricular hypertrophy and right heart failure. Pulmonary vascular smooth muscle hypertrophy and increased oxidative stress are major pathological features of PH. As available limited therapeutic options fail to reduce the mortality associated with PH, alternative areas of therapy are worth exploring for potential drugs, which might be beneficial in PH. AIM OF THE STUDY The effect of a standardised aqueous extract of the stem bark of Terminalia arjuna (Roxb.) in preventing monocrotaline (MCT)-induced PH in rat was investigated. MATERIALS AND METHODS The study was approved by Institutional Animal Ethics Committe. Male Wistar rats (150-200g) were randomly distributed into five groups; Control, MCT (50mg/kg subcutaneously once), sildenafil (175µg/kg/day three days after MCT for 25 days), and Arjuna extract (TA125 and TA250 mg/kg/day orally after MCT for 25 days). PH was confirmed by right ventricular weight to left ventricular plus septum weight (Fulton index), right ventricular systolic pressure (RVSP), echocardiography, percentage medial wall thickness of pulmonary arteries (%MWT). Oxidative stress in lung was assessed by super oxide dismutase (SOD), catalase, reduced glutathione (GSH) and thiobarbituric acid reactive substance (TBARS). The protein expressions of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX-1) in lung and gene expression of Bcl2 and Bax in heart were analyzed by Western blot and RT PCR respectively. RESULTS MCT caused right ventricular hypertrophy (0.58±0.05 vs 0.31±0.05; P<0.001 vs. control) and increase in RVSP (33.5±1.5 vs 22.3±4.7mm of Hg; P<0.001). Both sildenafil and Arjuna prevented hypertrophy and RVSP. Pulmonary artery acceleration time to ejection time ratio in echocardiography was decreased in PH rats (0.49±0.05 vs 0.32±0.06; P<0.001) which was prevented by sildenafil (0.44±0.06; P<0.01) and TA250 (0.45±0.06; P<0.01). % MWT of pulmonary arteries was increased in PH and was prevented by TA250. Increase in TBARS (132.7±18.4 vs 18.8±1.6nmol/mg protein; P<0.001) and decrease in SOD (58.4±14.1 vs 117.4±26.9U/mg protein; P<0.001) and catalase (0.30±0.05 vs 0.75±0.31U/mg protein; P<0.001) were observed in lung tissue of PH rats, which were prevented by sildenafil and both the doses of Arjuna extract. Protein expression of NOX1 was significantly increased in lung and gene expression of Bcl2/Bax ratio was significantly decreased in right ventricle in MCT-induced PH, both were significantly prevented by Arjuna and sildenafil. CONCLUSIONS Aqueous extract of Terminalia arjuna prevented MCT-induced pulmonary hypertension which may be attributed to its antioxidant as well as its effects on pulmonary arteriolar wall thickening.

Modified Blalock Taussig shunt: Comparison between neonates, infants and older children

OBJECTIVE The aim was to compare various pre-and post-operative parameters and to identify the predictors of mortality in neonates, infants, and older children undergoing Modified Blalock Taussig shunt (MBTS). MATERIALS AND METHODS Medical records of 134 children who underwent MBTS over a period of 2 years through thoracotomy were reviewed. Children were divided into three groups-neonates, infants, and older children. For analysis, various pre-and post-operative variables were recorded, including complications and mortality. RESULTS The increase in PaO 2 and SaO 2 levels after surgery was similar and statistically significant in all the three groups. The requirement of adrenaline, duration of ventilation and mortality was significantly higher in neonates. The overall mortality and infant mortality was 4.5% and 8%, respectively. CONCLUSION Neonates are at increased risk of complications and mortality compared with older children. Age (<30 days), weight (<3 kg), packed red blood cells transfusion >6 ml/kg, mechanical ventilation >24 h and post shunt increase in PaO 2 (P Diff) <25% of baseline PaO 2 are independent predictors of mortality in children undergoing MBTS.

Comparison of levosimendan and nitroglycerine in patients undergoing coronary artery bypass graft surgery

Background: Levosimendan a calcium ion sensitizer improves both systolic and diastolic functions. This novel lusitropic drug has predictable antiischemic properties which are mediated via the opening of mitochondrial adenosine triphosphate-sensitive potassium channels. This action of levosimendan is beneficial in cardiac surgical patients as it improves myocardial contractility, decreases systemic vascular resistance (SVR), and increases cardiac index (CI) and is thought to be cardioprotective. We decided to study whether levosimendan has any impact on the outcomes such as the duration of ventilation, the length of Intensive Care Unit (ICU) stay, and the hospital stay when compared with the nitroglycerine (NTG), which is the current standard of care at our center. Materials and Methods: Forty-seven patients undergoing elective coronary artery bypass surgery were randomly assigned to two groups receiving either levosimendan or NTG. The medications were started before starting surgery and continued until 24 h in the postoperative period. Baseline hemodynamic parameters were evaluated before beginning of the operation and then postoperatively at 3 different time intervals. N-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) levels were also measured in both groups. Results: In comparison to the NTG group, the duration of ventilation and length of ICU stay were significantly less in levosimendan group (P < 0.05, P = 0.02). NT-proBNP level analysis showed a slow rising pattern in both groups and a statistically significant rise in the levels was observed in NTG group (P = 0.03, P = 0.02) in postoperative period when compared to levosimendan group of patients. Conclusion: Levosimendan treatment in patients undergoing surgical revascularization resulted in improved CI, decreased SVR and lower heart rate. And, thereby the duration of ventilation and length of ICU stay were significantly less in this group of patients when compared with NTG group.

Minimally invasive cardiac surgery and transesophageal echocardiography

Improved cosmetic appearance, reduced pain and duration of post-operative stay have intensified the popularity of minimally invasive cardiac surgery (MICS); however, the increased risk of stroke remains a concern. In conventional cardiac surgery, surgeons can visualize and feel the cardiac structures directly, which is not possible with MICS. Transesophageal echocardiography (TEE) is essential during MICS in detecting problems that require immediate correction. Comprehensive evaluation of the cardiac structures and function helps in the confirmation of not only the definitive diagnosis, but also the success of surgical treatment. Venous and aortic cannulations are not under the direct vision of the surgeon and appropriate positioning of the cannulae is not possible during MICS without the aid of TEE. Intra-operative TEE helps in the navigation of the guide wire and correct placement of the cannulae and allows real-time assessment of valvular pathologies, ventricular filling, ventricular function, intracardiac air, weaning from cardiopulmonary bypass and adequacy of the surgical procedure. Early detection of perioperative complications by TEE potentially enhances the post-operative outcome of patients managed with MICS.

Multiple ruptured aneurysm of left sinus of valsalva: a rare entity.

Aneurysm of sinus of Valsalva is a rare congenital cardiac defect that can present with myriad signs and symptoms ranging from trivial to catastrophic events like cardiogenic shock and death. As clinical examination is not entirely reliable and the patient can sometimes be so ill as to preclude cardiac catheterization, echocardiography has become the definitive investigative tool not only to define and diagnose the lesion but also to quantify its severity. The following is a case report of multiple aneurysms of the left aortic sinus of Valsalva rupturing into the left ventricle. Diagnosis is made on multi plane transesophageal echocardiography and color Doppler regarding precise identification of structural anomalies and shunt locations for perioperative assessment and definitive treatment is surgical repair.