Tachycardiac storm in infant with WPW syndrome: "rescue" radiofrequency ablation.

A two-month-old child having WPW syndrome and orthodromic tachycardia was on treatment with digoxin, flecainide and amiodarone. Despite this, he continued to have severe, very frequent episodes of tachycardia. The left-sided accessory pathway was hence ablated via a patent foramen ovale.

Stenting for SVC obstruction in an infant operated for total anomalous pulmonary venous return.

Superior vena cava obstruction following corrective repair of total anomalous pulmonary venous return has rarely been described in the literature. A one-month-old boy who underwent corrective surgery for obstructive supracardiac total anomalous pulmonary venous return with consequent symptomatic superior vena cava obstruction in the immediate postoperative period, is reported. This was treated by balloon dilatation followed by stenting of the superior vena cava. The immediate postoperative result was satisfactory and the infant continued to remain asymptomatic at six months follow up. We suggest that this intervention could prove to be a viable alternative to a repeat surgical procedure for such complex cases.

Treatable cardiomyopathies.

Cardiomyopathy is defined as primary myocardial dysfunction which is not due to hypertensive, valvular, congenital, coronary or pulmonary vascular disease. This term usually denotes a dismal prognosis short of cardiac transplantation. However, several organic diseases of the heart can result in right or left ventricular dysfunction resulting in congestive heart failure and prompting the physician to label them as cardiomyopathy; the etiological factor is overlooked as it produces very subtle features. Therefore, before labelling any child as cardiomyopathic, all possible causes of ventricular dysfunction must be excluded by clinical and investigative means. The causes of "treatable cardiomyopathy" include mechanical factors as critical aortic stenosis and pulmonic stenosis, severe coarctation of aorta in an infant and aortaarteritis is an older child. Some of the persistent arrhythmias like atrial tachycardia, fibrillation, paroxysmal junctional re-entrant tachycardia are also known for causing ventricular dysfunction producing tachycardiomyopathy. Treatment of arrhythmia improves the ventricular function. Myocardial ischemia as a result of congenital coronary anomaly (commonest being anomalous origin of left coronary artery from pulmonary artery) can also present with a cardiomyopathy like picture. Early surgical correction is very rewarding. Finally, some of the metabolic conditions like creatinine and thiamine deficiency can also produce ventricular dilatation and dysfunction. In conclusion, the so called cardiomyopathy like picture can be produced because of several reasons and an attempt must be made to identify them.

Treatable cardiomyopathies.

Cardiomyopathy is defined as primary myocardial dysfunction which is not due to hypertensive, valvular, congenital, coronary or pulmonary vascular disease. This term usually denotes a dismal prognosis short of cardiac transplantation. However, several organic diseases of the heart can result in right or left ventricular dysfunction resulting in congestive heart failure and prompting the physician to label them as cardiomyopathy; the etiological factor is overlooked as it produces very subtle features. Therefore, before labelling any child as cardiomyopathic, all possible causes of ventricular dysfunction must be excluded by clinical and investigative means. The causes of "treatable cardiomyopathy" include mechanical factors as critical aortic stenosis and pulmonic stenosis, severe coarctation of aorta in an infant and aortaarteritis is an older child. Some of the persistent arrhythmias like atrial tachycardia, fibrillation, paroxysmal junctional re-entrant tachycardia are also known for causing ventricular dysfunction producing tachycardiomyopathy. Treatment of arrhythmia improves the ventricular function. Myocardial ischemia as a result of congenital coronary anomaly (commonest being anomalous origin of left coronary artery from pulmonary artery) can also present with a cardiomyopathy like picture. Early surgical correction is very rewarding. Finally, some of the metabolic conditions like creatinine and thiamine deficiency can also produce ventricular dilatation and dysfunction. In conclusion, the so called cardiomyopathy like picture can be produced because of several reasons and an attempt must be made to identify them.

Obstructive total anomalous pulmonary venous drainage.

Obstructive total anomalous pulmonary venous drainage (TAPVD) has a florid presentation in the neonatal period from the resulting pulmonary edema. A complete anatomical and functional diagnosis is usually possible by transthoracic color Doppler echocardiography, and cardiac catheterization with its attendant risks can usually be avoided in the sick neonate. Currently balloon atrial septostomy has a limited role in palliation of these neonates. Corrective surgery on urgent basis has gratifying results and prevents progression of pulmonary vascular occlusive disease. Pulmonary hypertensive crisis in the early post-operative course needs to be avoided and treated vigorously if it were to develop. Late post-operative course can be complicated by anastomotic obstruction or progressive narrowing of the individual pulmonary veins. Although the former can be dealt successfully by re-operation, surgical treatment of the latter is not satisfactory. Balloon dilatation of the obstructed pulmonary venous pathways, native and post-operative, has been reported with equivocal results. Infant heart-lung transplant is a viable option in patients with diffusely narrow pulmonary veins or complex TAPVDs.

Acute hemodynamic response to vasodilators in primary pulmonary hypertension.

Acute hemodynamic effects of high flow oxygen (O2) inhalation, sublingual isosorbide dinitrate (ISDN), intravenous aminophylline (AMN) and sublingual nifedipine (NIF) were studied in 32 patients with primary pulmonary hypertension (PPH). In 30 out of 32 patients the basal ratio of pulmonary to systemic vascular resistance (Rp/Rs) was > 0.5 (mean = 0.77 +/- 0.20). Oxygen caused significant decrease in the mean resistance ratio to 0.68 +/- 0.20 (p = 0.005). ISDN, AMN and NIF caused increase in the resistance ratio to 0.79 +/- 0.26; 0.78 +/- 0.26; and 0.80 +/- 0.23 respectively. O2, ISDN, AMN and NIF caused a fall of Rp/Rs in 21 (65.6%), 10 (31.2%), 10(31.2%) and 9(28.1%) patients respectively. Thus, of the four drugs tested high flow O2 inhalation resulted in fall of Rp/Rs in two thirds of patients whereas ISDN, AMN and NIF caused a mean rise in Rp/Rs. One third of patients did respond acutely to the latter three drugs. Acute hemodynamic studies are useful before prescribing vasodilators in patients with PPH since more of the commonly used drugs like ISDN, AMN, NIF could have detrimental hemodynamic responses in some patients. However, great caution should be exercised before performing hemodynamic study as the procedure has definite mortality and morbidity.

Effect of Blalock Taussig shunt on clinical parameters, left ventricular function and pulmonary arteries.

Twenty children (mean age 3.25 years) with congenital cyanotic heart disease undergoing modified left Blalock-Taussig (BT) shunt were studied. The mean follow-up period was 9.5 months (range 6 months to 1 year). The shunt was performed for cyanotic spells in 15 (75%) and hypoplastic pulmonary arteries in 5 (25%) patients. There were no immediate or late complications. None had cyanotic spell after the shunt. The mean arterial oxygen saturation improved from 66.47 +/- 11.9 to 76.97 +/- 8.16% (p = 0.0003) and mean hematocrit decreased from 51.55 +/- 9.5 to 46.5 +/- 9.7 (p = 0.002) after the shunt. The left atrial systolic volume and left ventricular diastolic volume also increased significantly following the shunt (from 15.82 +/- 6.37 to 20.83 +/- 8.91 ml p = 0.006 and from 36.13 +/- 16.08 to 41.08 +/- 20.07 ml (p = 0.01) respectively. There was significant growth of main, right and left pulmonary arteries and pulmonary valve annulus after the procedure.

Intrapulmonary vascular dilatations with hypoxemia in extrahepatic portal vein obstruction.

Several mechanisms have been suggested for the development of hypoxemia in cirrhosis. A few patients of portal hypertension due to non cirrhotic liver disease with cyanosis have also been reported earlier. We report probably the first documented case of portal hypertension with portal cavernoma and a normal liver, who had intrapulmonary vascular dilatations leading to hypoxemia and cyanosis. Our case suggests that changes leading to hypoxemia can occur due to portal hypertension alone, in the presence of a normal liver.

What should be called a brisk 'Y' descent?

Patients with pericardial constriction show a prominent 'y' descent in right atrial and vena caval pressure traces. In all earlier hemodynamic descriptions of constrictive pericarditis, the 'y' descent has been described as 'brisk', 'sharp' or 'rapid' but no effort has been made to quantify the same. In this study, we have tried to objectively evaluate and describe this 'y' descent by measuring its negative slope (-dy/dt) at its steepest portion. Forty one patients were studied hemodynamically, 9 with constrictive pericarditis (Group I) and 32 normals (Group II). The negative slope of the 'y' descent in patients with constrictive pericarditis (69.95 +/- 23.04 mm Hg) was found to be significantly greater than normals (35.13 +/- 7.84 mm Hg, p < 10(-6). Discriminant analysis was used to determine its sensitivity, specificity, predictive value and overall accuracy, in the diagnosis of pericardial constriction. Value of > or = 45 mm Hg/sec was found to have the highest overall accuracy (0.88). The correlation between the right ventricular end diastolic pressure and the slope of 'y' descent in patients with pericardial constriction (r = 0.66) and in normals (r = 0.60) was fair. It is concluded that -dy/dt is significantly different in patients with constrictive pericarditis as compared to normals. The diagnostic utility of this parameter needs to be evaluated in patients with equivocal clinical and hemodynamic data, in those with occult pericardial constriction and in post-pericardiectomy cases where the pressures do not normalise immediately after adequate pericardial resection.

Balloon angioplasty for native aortic coarctation.

From May 1987 to August 1990, eighteen patients underwent balloon angioplasty for native aortic coarctation. The age of the patients ranged from four to fifty six years (mean age 17.5 years). The procedure was successful in all cases with a reduction in the peak gradient across the coarctation from 61 +/- 19 mm Hg to 11.7 +/- 8.1 mmHg (p < 0.05). The coarcted segment increased from 4.5 +/- 1.9 mm to 10.7 +/- 3.9 mm (p < 0.05). Peak gradient at six to twelve months follow up, obtained in ten patients, was 19.8 +/- 10.1 mmHg (p = NS). There were no life threatening complications, although seven patients had local vascular problems after the procedure. In two patients, there was persistence of hypertension necessitating drug therapy. On haemodynamic and angiographic restudy in 10 patients, one patient had restenosis and none had aneurysm formation. We conclude that balloon angioplasty is a safe, and less invasive alternative to surgery for native aortic coarctation with gratifying immediate and short term results.