S. Radhakrishnan

Use of dopamine in prevention of contrast induced acute renal failure — A randomised study

We report the use of dopamine in renal doses (5 micrograms/kg/min) to prevent contrast induced nephropathy (CIN). Forty patients with diabetes mellitus who were undergoing coronary angiography were randomly divided into two groups. Gr I (20 patients) was infused with dopamine starting 30 min before cardiac catheterization and continued for 6 h thereafter. Gr II (20 patients) did not receive dopamine. Baseline blood chemistry was performed before catheterization and then repeated 24 h after the procedure. The mean age and sex distribution were similar in both the groups. Urograffin (76%; 120-150 ml) was used in all the cases. The mean serum creatinine and blood urea nitrogen (BUN) levels in Gr I patients before catheterization were 1.5 +/- 0.32 mg % and 16.3 +/- 8.05 mg %, respectively. The corresponding values for Gr II were 1.52 +/- 0.68 mg % and 19.6 +/- 13.4 mg %, respectively. After angiography, Gr I patients did not show significant changes in renal parameters (serum creatinine, 1.37 +/- 0.25 mg % and BUN, 14.7 +/- 5.5 mg %) while Gr II patients showed a significant rise (serum creatinine, 1.96 +/- 1.2 mg % and BUN, 23.25 +/- 12.7 mg %; P = 0.01 and P = 0.05, respectively). Ten patients in Gr II (50%) developed a 25% rise in serum creatinine levels within 24 h of injection of the contrast. None of the patients developed renal failure severe enough to warrant dialysis. Hence alterations of renal function are common after cardiac catheterization. Dopamine in renal doses appears to be an effective means to prevent deterioration in renal function induced by contrast.

Dextrocardia: an analysis of cardiac structures in 125 patients

BACKGROUND Dextrocardia is associated with multiple and complex congenital cardiac anomalies. Precise anatomical diagnosis is essential for successful surgery. Spectrum of congenital malformations in cases of dextrocardia is based primarily on two-dimensional echocardiographic studies. The purpose of the current study was to use colour Doppler echocardiography in large number of patients. METHODS Patients of dextrocardia were studied retrospectively, by reviewing database of our echocardiographic laboratory over last 10 years. Standard criteria for diagnosis of situs were used. Detailed segmental analysis for cardiac anatomy and associated malformations was done using previously suggested and well accepted terms and definitions. Cardiac anatomy was confirmed on catheterization and during surgery in few cases. RESULTS Of total 125 patients, dextrocardia was most common with situs inversus (39.2%) followed by situs solitus (34.4%) and situs ambiguous [26.4% (right isomerism in 18.4% and left isomerism in 8.0%)]. Mean age was 9.2+/-11.2 years (range; 3 days to 60 years), 82 males and 43 females. In situs inversus dextrocardia, majority (73.4%) had concordant atrioventricular (AV) connections while discordant AV connections and univentricular atrioventricular connections (UVAVC) were present in 12.2 and 14.3% patients, respectively. Majority of patients with concordant AV connections (72.2%) also had concordant VA (ventriculo-arterial) connections (conotruncal anomalies were commonest). Similarly, majority of patients with discordant AV connections (66.7%) also had discordant VA connections. Commonly (44.9%), these patients presented with decreased pulmonary blood flow (Qp). Total 28.6% patients had normal intracardiac anatomy (10.2% presented with rheumatic heart disease). In situs solitus dextrocardia, majority (51.2%) had AV concordance while discordant AV connections and UVAVC were present in 41.9 and 7.0% patients, respectively. In patients with concordant AV connections, majority (77.2%) had VA concordance (majority presented with increased Qp due to pre or post-tricuspid shunts). Similarly, majority of patients with discordant AV connections (88.9%) also had discordant VA connections (88.9% presented with decreased Qp). Only 7.0% patients with situs solitus dextrocardia had normal intracardiac anatomy. The striking features of right isomerism were male predominance (male:female ratio 2.2:1), cyanosis with decreased Qp in 86.9%, and high incidence of UVAVC and venous system anomalies (39.1% each). Striking features of left isomerism were biventricular ambiguous AV connections in all except one, presentation with increased Qp in 60.0% and presence of inferior vena caval interruption in 60.0% patients. CONCLUSIONS Present study, largest study of dextrocardia till date reconfirms that these patients have variable intracardiac anatomy depending upon their situs and types of segmental connections. These patients can present with different haemodynamic subsets, which can be correctly identified by colour Doppler echocardiography. Diagnostic accuracy and a better understanding of the various types of dextrocardia are essential, since improved surgical techniques have made it possible to correct many of these complex abnormalities.

Total Intravenous Anesthesia With Ketamine for Pediatric Interventional Cardiac Procedures

OBJECTIVE To evaluate the safety and efficacy of ketamine in pediatric patients undergoing interventional cardiac procedures. DESIGN A retrospective clinical study. SETTING A single, tertiary referral center. PARTICIPANTS Patients (n = 107) undergoing interventional cardiac procedures between July 1996 and July 1998. INTERVENTIONS Each patient received a bolus of ketamine, 1 mg/kg intravenously, followed by an infusion of 50 to 75 microg/kg/min for the duration of the procedure. MEASUREMENTS AND MAIN RESULTS Hemodynamic and respiratory parameters were noted. All patients were breathing spontaneously. Average infusion dose of ketamine was 51.40+/-3.54 microg/kg/min (mean +/- standard deviation). Increases in heart rate and mean arterial pressure by more than 20% from baseline values were seen in 10 and 9 patients, respectively. Transient apnea and excessive salivation were seen in two patients each. Excessive movement of extremities was seen in six patients. There were no episodes of unpleasant dreams or hallucinations. There were two deaths (1.9%) related to the interventional procedures. CONCLUSION The technique described is a simple, safe, and effective method for anesthetizing children in the cardiac catheterization laboratory for interventional procedures.

Immediate and early results of closure of moderate to large patent arterial ducts using the new Amplatzer device.

OBJECTIVES Our aim was to assess the immediate and short term results of closure of moderate and large patent arterial ducts using the self-expanding and repositionable Amplatzer device. METHOD We attempted closure in 25 patients (10 Females and 15 males) using the Amplatzer occluder. Their median age was 48 months with a range from 8 months to 26 years and median weight of 14 kg with a range from 4.5 kg to 48 kg. The mean ductal diameter was 4.1 mm (S.D 1.51 mm). A 6F/7F long sheath was used to deliver the device. Follow up was performed with colour- flow mapping of the pulmonary trunk within 24 hours, at 3 months, and 6 months of closure. RESULTS Of the 25 patients, the device was placed successfully in 23. Concurrent angiography showed immediate closure in 12 patients, while 8 had trivial shunting and 3 had mild shunting. Within 24 hours, Doppler examination revealed complete closure in all but three patients, who had a mild residual shunt. Two attempts were unsuccessful. Both these patients underwent successful surgical ligation. All except one patient were discharged on the next day. Of the 23 patients, 15 (65%) have been followed up for 3 months, while 8 (35%) have completed 6 months of follow-up. Of the three patients initially with mild residual flow, two had completely closed at 3 months The one remaining patient is yet to be seen at the 3 month follow-up. Thus, at 3 months, all patients studies had shown complete closure. CONCLUSION Antegrade transcatheter closure using the Amplatzer duct occluder is an efficacious treatment for bigger patent arterial ducts. Long-term follow-up is necessary to show sustained benefits and confirm the absence of side effects.

Infective endocarditis following patch closure of ventricular septal defect: a cross-sectional Doppler echocardiographic study

Cross-sectional and Doppler echocardiographic characteristics of infective endocarditis are described in six cases following patch closure of a ventricular septal defect. The patients presented to us with fever one to five months after surgery. Five of them also had congestive cardiac failure. Cross-sectional echocardiography showed large masses over the patch in all cases. Dehiscence of the lower end of the patch was identified in three of them, and, in two cases, the right sinus of Valsalva had ruptured into the right ventricle. Doppler detected turbulent flow in the right ventricle in five cases, and a continuous signal indicating an aorto-right ventricular communication in two cases. A signal indicative of aortic regurgitation was also found in the latter two cases. Staphylococcus aureus was cultured from the blood in three cases and Aspergillus was identified at autopsy in one. The echocardiographic findings were confirmed in three cases (one during surgery and two at autopsy). Dehiscence of the patch and large masses were associated with a poor prognosis.

Response of different grades of pulmonary artery hypertension to balloon mitral valvuloplasty.

fore, they speculated about synergistic effects of plasminogen and adverse alterations of lipid metabolism on cardiovascular risk. We have also found a weak correlation between markers of lipid metabolism and plasminogen; however, adjustment for high-density lipoprotein cholesterol did not significantly change the odds ratio. Additional adjustment for lipoprotein(a), which may compete with plasminogen for binding to lysine residues because of its structural homology,11 also did not significantly change the odds ratio. Although the main result is a negative one, our study had a power of 80% to detect an odds ratio of 1.65 ( 0.05) (associated with quartiles 4 vs 1).

Non-surgical closure of large ductus arteriosus using Amplatzer Duct Occluder feasibility and early follow-up results.

The aim of the study was the assess feasibility of closing large patent arterial ducts (PDA) in infants and children using the new Amplatzer Duct Occluder. All patients diagnosed to be having PDA were considered as potential candidates to undergo the device closure. 19 patients were diagnosed to be having PDA larger than 4 mm. There were 10 males and 9 females, their age ranged from 6 months to 120 months with a mean of 45 months. Mean body weight was 14.5 kg with a range from 7 kg to 23 kg. The procedure was carried out under Ketamine sedation and local anesthesia. The device was implanted by the transvenous route in all. Mean PDA diameter was 5 mm (range 4 mm-6.7 mm). Complete closure was achieved in 16J18 (88%) within 24 hours of the procedure. All patient have been followed for 3 months, and have documented complete closure, there is no evidence of aortic or left pulmonary stenosis in any of our patients. The unsuccessful attempt was in a malnourished patient (weighing 4.7 kg) with an arterial duct measuring 6.7 mm on angiography. This duct was considered too big for device closure and the procedure was abandoned. This patient subsequently has undergone successful surgical ligation. Catheter closure of large PDA in small children is feasible, safe and efficacious. However, it may still not be possible to close large PDA in very small or underweight children, for the fear of causing obstruction to the descending aorta. Further long-term is follow-up required to show sustained benefits without any side effects.

Unusual presentation during childhood of left ventricular myxoma.

Amongst all primary cardiac tumors, myxomas are the commonest, and their commonest site of origin is the left atrium. Myxomas originating in the left ventricle are rare. When seen, they usually present with a history of systemic embolisation and/or syncopal episodes, with constitutional symptoms being absent. We report here a child with left ventricular myxoma who presented with a prolonged febrile illness.

Acute pulmonary oedema following percutaneous balloon pulmonary valvoplasty in children.

Pulmonary oedema complicating balloon dilation of the pulmonary valve is extremely rare. We describe two children who developed acute pulmonary oedema soon after successful dilation of the pulmonary valve. They were treated with diuretics, ionotropes, and ventilatory support. Despite the supportive therapy, the complication proved fatal in one.

Three dimensional transesophageal echocardiography guided transcatheter closure of mitral paraprosthesis regurgitation – A case report

The last two decades have witnessed vast advances in the field of cardiac intervention, particularly with regard to nonsurgical closure of structural heart diseases including para prosthetic valvular leaks. The use of imaging techniques to guide even well-established procedures enhances the efficiency and safety of these procedures. The present case report aims to highlight the role of three dimensional transesophageal echocardiography in pre, intra and post operative management of patients with mitral para prosthetic valvular regurgitation.