Bidirectional Glenn shunt: a step in the right direction.

Bidirectional Glenn (BDG) shunt was carried out in 14 patients (age range 1.5-22 years; mean 9.3 years) for a variety of congenital cyanotic heart diseases with decreased pulmonary blood flow. Postoperative cardiac catheterisation was carried out in 10 patients including successful balloon angioplasty of the shunt and LPA in one patient. There was a significant improvement in oxygen saturation and a drop in haematocrit level at follow-up. Doppler echocardiography studies in 13 patients revealed functioning shunts in all cases with low velocity continuous flow. Thus BDG is a useful palliative procedure and could be undertaken as the first stage of total cavopulmonary connection in high-risk Fontan groups where biventricular repair is not feasible.

Blade and balloon atrial septostomy for creation of an adequate interatrial communication.

During a 7 year period from 1984 to 1991, 100 infants underwent either balloon atrial septostomy (BAS) (n = 92) or blade septostomy (BLS) (n = 8). The indication was complete transposition of the great arteries in all the patients. The mean age in the BAS group was 1.8 +/- 1.5 months while that in the infants requiring BLS due to a thick septum was 3.03 +/- 2.29 months. The degree of improvement in arterial oxygen saturation in both groups was satisfactory -27.16 +/- 14.06% in the BAS group vs 23.5 +/- 12.18% in the BLS group. There were no procedure related deaths in the BLS group, through only monoplane fluoroscopy was used in 6/8 patients. Three patients however died following balloon septostomy. We conclude that BLS is a safe and effective alternative to surgical septostomy when performed with due care. Two dimensional echocardiography during BAS enhances the speed and safety of the procedure and helps to identify patients who may require BLS due to a thick interatrial septum.

Primary pulmonary hypertension: natural history and prognostic factors.

A retrospective cohort study was carried out in 61 patients (30 males, 31 females, age 24.6 +/- 11.8 years) with primary pulmonary hypertension diagnosed by strict clinical and hemodynamic criteria, to obtain an understanding of the natural history and prognostic markers. While 15 patients were alive, 46 patients (76%) had expired during the follow up period. Two, five and ten years survivals were 48%, 32% and 12% respectively. Median survival duration from time of diagnosis was 22 months. The survivors had significantly higher age of onset, cardiac index and significantly lower right atrial mean pressure, right ventricular end diastolic pressure, cardiothoracic ratio from chest rontgenogram and calculated pulmonary vascular resistance as compared to non survivors. While pulmonary artery systolic pressure was not significantly different, pulmonary artery diastolic and pulmonary artery mean pressures were significantly lower in survivors than in non-survivors. Lower New York Heart Association class, right atrial mean pressure < or = 7 mm Hg, right ventricular end diastolic pressure < or = 10 mmHg, cardiac index > 2.5 L/min/m2, pulmonary arterial oxygen saturation > 60%, were associated with significantly longer survival. The degree of pulmonary arterial hypertension had an indirect prognostic effect through the above parameters. Vasodilator therapy did not significantly alter the outcome of patients with primary pulmonary hypertension.

Thrombolytic therapy for prosthetic cardiac valve thrombosis.

During 1992-93 12 patients (5 males, 7 females) with thrombosed prosthetic cardiac valves were treated with streptokinase on 13 occasions (one patient with prosthetic tricuspid valve had two thrombotic episodes). Their age ranged from 14 to 52 years (median 39). Two valves were in aortic position, six in mitral and four in tricuspid position. Eight were Bjork-Shiley prosthesis, three were Medtronic Hall valves and one was a St. Jude Valve. Timing of prosthetic valve thrombosis ranged from 3 months to 12 years after valve replacement surgery. Duration of symptoms due to valve thrombosis ranged from 1-4 months with tricuspid valve thrombosis and 1-14 days with left sided valve thrombosis. Five were in functional class II and four each were in functional class III and class IV. All patients were evaluated by echo Doppler and cine fluoroscopy. Loading dose of streptokinase was 2.5 lakh units in 4 patients and 1 lakh units in 9 patients. Maintenance infusion was at 1000 units/Kg/hour in 11 patients and 1 lakh units/hour in 2 patients. Duration of streptokinase infusion ranged from 3 hr to 38 hr. Thrombolytic therapy was successful (clinical, echo Doppler and fluoroscopy) in 12 out of 13 cases (92%). It was unsuccessful in a patient with valve at tricuspid position in whom infusion had to be stopped after 24 hour due to bleeding gums. One patient developed intracerebral bleed and expired. In conclusion streptokinase therapy is useful for prosthetic cardiac valve thrombosis.

Enhanced lipid peroxidation in patients during coronary artery bypass grafting.

Lipid peroxidation products were measured at various time intervals in 20 patients with coronary artery disease, who underwent coronary artery bypass graft (CABG) surgery. Post-operative blood lipid peroxides were found to be significantly higher (p < 0.001) than the preoperative value. Lipid peroxides raised to a peak value of 46.42 +/- 12.86 n mol/g Alb at 5 min of reperfusion when compared to the basal value and afterwards the level declined to 41.02 +/- 7.09 at 2 hrs and remained in that level even at 24 hrs of reperfusion. This increase implies an enhancement in free radical mediated oxidation of membrane lipids during bypass surgery and thus provides evidence for free radical generation during myocardial reperfusion.

Distribution of cholesterol in HDL and its subfractions in patients with coronary atherosclerotic heart disease.

The distribution of HDL-C and its subclasses HDL3-C and HDL2-C and other serum lipids was studied in patients with coronary atherosclerotic heart disease grouped as young males (group 1) and older males (group 2) along with age matched controls. All the patients had significantly higher levels of serum cholesterol, triglycerides, LDL-C and VLDL-C and lower levels of HDL-C. The analysis of HDL - subclasses clearly demonstrated that the low levels of HDL-C was due to the significant decrease of cholesterol in both HDL3 (group 1: 32%; group 2: 30%) and HDL2 subclasses (group 1: 55%; group 2: 48%) compared to the respective control values. Further it has also been observed that this low level of HDL-C is a characteristic feature of patients irrespective of whether the levels of serum cholesterol and triglycerides are high or normal. Although both the HDL subclasses were decreased, the percentage of reduction of cholesterol was greater in the HDL2 than in HDL3 subclass. In addition, the levels of cholesterol either in HDL or any of its subclasses, HDL3 and HDL2 did not show any change in relation to the extent of coronary disease which was assessed by coronary angiography. This study confirms the inverse relation of HDL-C with coronary atherosclerosis and also indicates that, of all the lipid parameters examined, only HDL-C, particularly its subclass HDL2-C, shows independent inverse relation to the incidence of coronary atherosclerotic artery disease in men.

Two dimensional and Doppler echocardiographic evaluation of double chambered right ventricle.

Two-dimensional and Doppler echocardiographic findings in 20 patients with double chambered right ventricle are described. All patients had the diagnosis established by cardiac catheterisation and confirmed at operation. Echocardiographic evaluation was done prior to surgical correction. Anomalous muscle bands in right ventricular cavity were detected in 16 patients. Doppler flow velocities in the right ventricular cavity suggested infundibular obstruction to blood flow at a low level in all 17 patients studied by Doppler echocardiography. Ventricular septal defects (11 patients), pulmonary stenosis (3 patients), and aortic regurgitation (3 patients) were detected accurately before operation by echocardiographic examination. Failure to detect the anomalous muscles in right ventricular cavity may occur in adult patients with poor anterior resolution and in those with severe right ventricular outflow obstruction and myocardial hypertrophy. Two dimensional echocardiography with Doppler flow analysis is useful in the evaluation and differential diagnosis of right ventricular outflow obstructions prior to invasive studies and surgical intervention.

Creatine kinase and its isoenzyme MB in patients after open heart surgery.

Total serum creatine kinase (CK) and its isoenzyme MB (CKMB) were measured before and 4, 24, 48 and 72 hours after termination of cardiopulmonary bypass in patients undergoing (I) atriotomy, (II) ventriculotomy and (III) coronary artery bypass surgery. All patients were free of postoperative complications and myocardial infarction as defined by clinical course, 12 lead ECG and 2D echocardiography. Peak elevation of CK occurred at 24th hour and CKMB at 4th hour and then gradually declined. There was no relation between the peak level of rise of CK or CKMB with cross clamp time or bypass time. The 96th percentile values of absolute CKMB level at 4, 24, 48 and 72 hours may suggest perioperative myocardial infarction with specificity of 95%. In addition, the rising value of CKMB beyond 24 hours after the termination of bypass may also suggest occurrence of myocardial infarction.

A correlative study of the functional class and hemodynamic status following intracardiac repair of tetralogy of Fallot.

An attempt was made to correlate the NYHA Functional class with the hemodynamic status of 196 patients at an average of 21.2 months following the intracardiac repair of tetralogy of Fallot. 171 patients were in Functional class I (87.2%), 9 in class III (4.5%), 5 in class II (2.5%) and 11 in class IV (5.6%). Right and left heart catheterisation and cardiac angiography revealed the hemodynamic status of these patients to be excellent in 92 (46.4%), good in 37 (18.8%), satisfactory in 6 (3.0%) and unsatisfactory in 61 (31.6%). Whereas all patients in Functional class II, III and IV had unsatisfactory hemodynamic findings, patients in Functional Class I were hemodynamically heterogeneous and included excellent (53.8%), good (21.6%), satisfactory (3.5%) and unsatisfactory (21%) groups. The surgical technique did not seem to determine the functional status. While early reoperation is advisable for patients with functional disability, caution is necessary in considering reoperation for patients in Functional class I who have hemodynamic findings which are classified as unsatisfactory.

Coxsackie viral myocarditis: a clinical and echocardiographic study.

Thirty two patients with acute onset of cardiac symptoms following an episode suggestive of viral infection, were studied. 11 patients had Coxsackie viral myocarditis. All had 4 fold rise of neutralising Coxsackie viral antibody titres on paired sera tested. Coxsackie B virus types 2 and 4 were commonly detected. Among the eleven patients, 8 presented with congestive heart failure, 2 with ventricular arrhythmias and one with chest pain and S3 gallop. All had ECG changes. Echocardiographic examination showed global left ventricular dysfunction in 7, regional wall motion abnormalities in 2 and normal left ventricular function in one. Serial echocardiographic examination showed progressive myocardial dysfunction in 3 and improvement in myocardial function in two patients. Two patients died during the follow up period. Echocardiography helped in assessing the course of patients with viral myocarditis.

Assessment of severity of aortic stenosis by continuous wave Doppler echocardiography.

Fifty consecutive patients with aortic stenosis were evaluated by continuous wave Doppler echocardiography for assessment of the transaortic gradient. The Doppler derived gradients were compared with the gradients measured at cardiac catheterisation. Excellent correlation was found between the Doppler and catheterisation findings for the maximum instantaneous gradient (r = 0.92) and the mean systolic gradient (r = 0.84). The maximum, midsystolic and late systolic Doppler gradients also showed a good correlation with the peak to peak catheter gradient. The maximum Doppler velocity however, showed overestimation of the peak to peak gradient in the presence of mild aortic stenosis (predictive accuracy 86%). The midsystolic Doppler velocity showed the highest predictive accuracy (94%) for the detection of severe aortic stenosis. No case of severe aortic stenosis was missed by Doppler using either the maximum or midsystolic Doppler velocity. These findings indicate that continuous wave Doppler ultrasound provides a reliable estimate of the gradient in patients with aortic stenosis.

Two-dimensional and Doppler echocardiographic study of coronary arteriovenous fistulas.

Sixteen patients with coronary arteriovenous fistula (CAVF) were studied by two-dimensional echocardiography (2DE). Of these 12 had Doppler studies. In all, the diagnosis of CAVF was confirmed by aortic root or selective coronary angiography. In 8 patients, the 2DE findings suggested CAVF. Five patients had dilated main coronary arteries and in 4 patients abnormal fistulous channels were identified. Two had diastolic flutter of the tricuspid valve and one had spontaneous contrast in the right atrium. In 11 out of 12 patients, Doppler analysis picked up a continuous flow (to the right atrium in 5, right ventricle in 4 and to both ventricles in 2 patients) prior to the cardiac catheterisation. We conclude that noninvasive diagnosis of CAVF can be made with the combined use of two-dimensional and Doppler echocardiography in most of the patients.

Double chambered right ventricle with anomalous muscle bundles and false tendons in the left ventricle.

A patient with double chambered right ventricle, with anomalous muscle bundles and false tendons in the left ventricle, is described. This combination of anomalies may represent a failure of regression of foetal trabeculations.

Accuracy of continuous wave Doppler predicted gradient in patients undergoing balloon pulmonary valvoplasty.

14 patients who underwent balloon valvoplasty had trans-pulmonic gradient evaluated by continuous wave Doppler echocardiography. Maximum systolic gradients measured from Doppler flow velocities were correlated with peak to peak gradient obtained at cardiac catheterisation. Prior to valvoplasty, there was good correlation between the Doppler maximum gradient (92.85 +/- 34.7mm Hg) and the peak to peak catheter gradient (105.57 +/- 56.60 mm Hg), (r = 0.91, p = less than 0.001). Immediately after balloon valvoplasty, the maximum Doppler gradient did not correlate with the peak to peak catheter gradient (r = 0.33, p = NS). Exclusion of patients with infundibular gradients improved the correlation coefficient between the Doppler maximum and peak to peak catheter gradient to 0.69. At late restudy following valvoplasty, when regression of infundibular stenosis was noted in 6 out of 8 patients, the Doppler maximum and catheter peak to peak gradient had excellent correlation (r = 0.97, p = less than 0.001). In patients with lone valvular gradient immediately following valvoplasty and at late restudy, maximum Doppler gradients correlated well with catheter gradients in 14 estimations (r = 0.66, p = less than 0.01). This study shows that the non-invasive quantification of pulmonary valve stenosis can be reliably undertaken, using continuous wave Doppler echocardiography before balloon valvoplasty and during follow-up, after the procedure when the infundibular stenosis has regressed. The presence of an infundibular gradient immediately after balloon dilatation makes the Doppler prediction less reliable.