Pulmonary embolism: an observational study at Narayana Hrudayalaya Institute of Cardiac Sciences, Bangalore, India.

Pulmonary embolism (PE) is extremely common and is a leading cause of death in all age groups. Unfortunately the diagnosis is most often missed than it is made. Prompt diagnosis and treatment can dramatically reduce the mortality and morbidity. This study was done to evaluate the patients with acute PE, assess the utility of laboratory tests and potential of high resolution spiral computed tomogram angiography of pulmonary arteries (sCTPA) as the confirmatory diagnostic tool. Twenty six consecutive patients with acute PE admitted to CCU of Narayana Hrudayalaya of Banglore were followed prospectively. There were 15 male and 11 female (M:F=1:3:1); age range was 32-58 yrs. (mean 45+/-13 yrs). Pre-testing probability assessment of PE was done by a combined approach of history, physical examination and presence of risk factors. D-dimer and cardiac troponin I (TnI) estimation and sCPTA done by contrast enhanced 64-slice spiral CT scanner in all patients. In addition to the typical findings of PE, sCTPA included and revealed features of cardiac and venous CT imaging. Doppler study of leg veins were done to exclude deep vein thrombosis. Trans-thoracic echocardiography assessed right ventricular dilatation and presence of pulmonary hypertension. Nineteen patients (73.0%) had sub-massive PE, 5 patients (19.2%) had non-massive and 2 patients (7.6%) presented with massive PE. A raised D-dimer (0.5mugm/ml) was found in all the cases (100.0%). An elevated a trponin I (TnI) was found in 18 patients (69.2%). RV dilatation, (i.e. RV/LV>0.9) was found in 21 patients (80.7%). All patients (100.0%) received unfractionated heparin. Thrombolysis with alteplase, without concomittent heparin was administered in 11 patients (42.3%). Inferior venacaval filter were implanted in 9 patients (34.6%) with sub massive PE and recurrent events despite anticoagulation. Embolectomy done in one patients with massive PE, offered satisfactory recovery. Pulmonary endarterectomy were undertaken in 6 patients with acute on chronic thromboembolic pulmonary hypertension. Thus sCTPA detected PE, source of PE and provided prognostic information.

Myocardial infarction and biventricular free-wall rupture with shunting through a false aneurysm.

A 65-year-old man presented with acute inferior myocardial infarction and received thrombolytic therapy with clinical evidence of coronary arterial recanalisation. Recovery was uncomplicated until- the eighth day when he experienced recurrent chest pain with evidence of reinfarction in the same territory. This was associated with the development of a pansystolic murmur and cardiogenic shock. Cardiac catheterisation showed right coronary arterial occlusion and inferior infarction with a false aneurysm and a left-to-right shunt (shunt ratio 2.5:1). Surgery confirmed the formation of a false aneurysm caused by rupture of the free walls of both ventricles. Importantly, however, the interventricular septum was intact and the left-to-right shunt was through the false aneurysm itself. This is the first report of biventricular free-wall rupture with shunting through a false aneurysm treated successfully by surgery.

Video-assisted thoracoscopic surgery for closure of patent ductus arteriosus in children.

Video-assisted thoracoscopic surgery (VATS) was recently described as an approach to clip the patent ductus arteriosus (PDA). Between May 1994 and May 1996, we performed this procedure on 34 children below 12 years of age (mean 7 years). Thirty-two had an isolated PDA and two had associated small perimembranous ventricular septal defect (VSD), diagnosed on echocardiography and colour flow mapping. None had pulmonary arterial hypertension. The procedure was successful in 33 (97%) children confirmed by absence of residual shunt on serial echocardiography. Complications in the form of pneumothorax (1) and vocal card paralysis (2) were encountered in three children. The overall hospital stay was reduced to five days. In conclusion, the technique of PDA clipping using VATS is easy to learn and highly successful with acceptable risk of complications.

Significance of exercise induced increase in diastolic pressure as an indicator of severe coronary artery disease.

A total of 100 patients were studied for the diastolic blood pressure response to treadmill exercise testing. No change in the diastolic pressure or lowering of the pressure was considered normal response. Seventy four patients had normal and 26 patients had abnormal diastolic blood pressure response. Out of these, 40 patients underwent coronary angiography. Fifty five percent of the patients with normal diastolic pressure response had normal coronaries compared to 20% with abnormal response (p < 0.03). Fifteen percent with normal response had triple vessel disease or left main coronary artery disease whereas forty percent with an abnormal response had significant disease (p < 0.03). Exercise induced ST segment depression was almost equal in both groups. Hence we can conclude that abnormal diastolic pressure response to treadmill exercise testing is a fairly good indicator of coronary artery disease irrespective of ST segment changes.

Candida tropicalis causing prosthetic valve endocarditis.

The incidence of endocarditis produced by the so-called "opportunists" as a complication of prosthetic valve surgery is progressively increasing in frequency and gradually transforming the clinical picture habitually associated with this disease. Candida endocarditis is an unusual but severe complication caused by Candida albicans or other fungal species. This case and a review of the literature indicate that Candida endocarditis treated with amphotericin B and prosthetic valve replacement may recur months after treatment, and that late recurrent Candida endocarditis, which is difficult to diagnose and treat, may be best prevented by lifelong antifungal suppressive therapy.

Ultra low dose aprotinin decreases blood loss and transfusion requirements in high risk two valve replacement surgery.

The efficacy of ultra-low-dose-aprotinin (ULDA) in 'high-risk' two valve replacement surgery, was evaluated in this prospective, randomized, double-blind study. Forty adult high-risk patients undergoing elective two valve replacement surgery, were included. The patients were divided into 2 groups of 20 each. In Group I, aprotinin in a dose of 1,000,000 KIU was administered from the end of anaesthesia induction to the time of sternotomy after a 1 ml of test dose. In Group II (control), 100 ml of normal saline was administered in a similar fashion. Coagulation parameters, blood loss, and amount of transfusion of blood / blood products were measured at specific intervals. The postoperative chest tube drainage in the first 24 hours was significantly less 203+/-35 ml (p<0.05) in Group I as compared with 490+/-104 ml in group II and consequently, Group I patients received significantly less (p<0.05) red cell concentrates and platelet transfusion. There was a significant decrease in the length of postoperative elective ventilation, intensive care unit (ICU) stay and direct costs involved in the hospital expenses with the use of ULDA. We conclude that ULDA is safe and effective in 'high-risk' two-valve replacement surgery to reduce postoperative bleeding, postoperative length of intubation and ICU stay; use of ULDA is associated with significant direct cost savings.

Ventilation strategy for video-assisted thoracoscopic clipping of patent ductus arteriosus in children.

Video-assisted endoscopic techniques have reduced operative trauma in adult thoracic and general surgery but its application in children with congenital heart disease has been limited. We report the use of video-assisted thoracoscopic (VAT) technique of clipping patent ductus arteriosus (PDA) in children. Forty patients with PDA were divided into two groups: during VAT surgery patients in group A [mean age=3.6 +/- 2.4 (SD) years] were managed with right main stem bronchial intubation and those in the group B [mean age=3.7 +/- 2.7 (SD) years] received low tidal volume-high frequency ventilation using a Siemens 900C ventilator. The mean oxygen saturation (SpO2) observed during the surgical intervention was significantly lower in group A (90%) compared to group B (96.8%) while the surgical convenience was not different. We conclude that a low tidal volume-high frequency ventilation is acceptable and safe in patients with PDA undergoing VATS.

Significance of exercise induced increase in the diastolic pressure as an indicator of severe coronary artery disease.

A total of 100 patients were studied for the diastolic blood pressure response to treadmill exercise testing. No change in the diastolic pressure or lowering of the pressure was considered normal response. Seventy-four patients had normal and 26 patients had abnormal diastolic blood pressure response. Forty patients underwent coronary angiography. Fifty-five per cent of the patients with normal diastolic pressure response had normal coronaries compared to 20% with abnormal response. Eleven per cent with normal response and 40% with an abnormal response had triple vessel disease whereas 10% with abnormal response had left main coronary artery disease. Exercise induced ST segment depression was almost equal in both groups. Hence it can be concluded that abnormal diastolic pressure response to treadmill exercise testing is a fairly good indicator of coronary artery disease irrespective of ST segment changes.

A safe technique to monitor pulmonary artery pressure during and after paediatric cardiac surgery.

Pulmonary hypertensive crises (PHC) are a recognized cause of sudden clinical deterioration and death after the surgical correction of congenital heart disease. In this study, pulmonary artery pressure was monitored in 84 children (at high risk to develop PHC) aged nine days to five years (mean 1.4 years) using monitoring lines inserted percutaneously through the right internal jugular vein (IJV). Success rate of placement of the catheter tip in the pulmonary artery (PA) in the pre-incision period was not high (7%) but all catheter-tips were successfully placed in the PA by the surgeon before right atrial closure prior to separation from cardiopulmonary bypass. Complications related to the technique were transient ventricular/atrial arrhythmias (78.5%) during insertion and slipping or coiling (20%) of the catheter in the right ventricle. Complications relating to the IJV puncture included carotid arterial puncture and pneumothorax. No other complications were encountered. Monitoring lines inserted percutaneously and guided into the pulmonary artery during surgery provide a safe and practical way of monitoring pulmonary artery in infants and children at risk of postoperative pulmonary hypertensive crises.

Biochemical Markers of Myocardial Injury during Coronary Artery Bypass Grafting with and without Cardiopulmonary Bypass.

Minimally invasive cardiac surgical techniques have been applied recently in the management of variety of cardiac lesions. Between December 1998 and February 1999, fifty patients underwent coronary artery bypass grafting (CABG) under two different techniques. In group A (twenty five patients), CABG was done under cardiopulmonary bypass (CPB) and in group B (twenty three patients), CABG was performed on a 'beating heart' without CPB. Serum concentration of cardiac specific enzymes CPZ-MB and Troponin-T were estimated in all the patients from pre-induction period to 72 hours after the bypass graft. Group A patients exhibited a significant (P<0.05) elevation in the CPK-MB and Troponin-T level as compared to group B. Our results show that the extent of myocardial damage following CABG is significantly less when the procedure is done on a 'beating heart'.