Novel arterioplasty of severe left pulmonary artery stenosis using native main pulmonary artery

There are multiple approaches described for the repair of stenosed branch pulmonary arteries. Regardless of the technique used, restenosis is common. We describe a case of severe left pulmonary artery stenosis repaired with a novel technique using the native main pulmonary artery which was transected and turned down to create a direct anastomosis with the left pulmonary artery. This tension-free tissue to tissue anastomosis resulted in hemodynamically gratifying results with the potential for growth.

One stage combined repair of intracardiac defects with vascular ring employing sternotomy approach

We present an unusual case of atrial septal defect and ventricular septal defect with a vascular ring formed by a right-sided aortic arch with an aberrant left subclavian artery that gave rise to a patent ductus arteriosus connecting to the main pulmonary artery. We performed a single-stage repair of the intracardiac defects and division of vascular ring with a sternotomy instead of the traditionally practiced dual approach. This included division and reimplantation of the aberrant left subclavian artery to the left carotid artery after transection. This approach has not been described so far.

Long-term follow-up of an adult with left pulmonary artery stenting and absent right pulmonary artery: a case report

Background

Unilateral absence of pulmonary artery is a rare congenital abnormality with varied clinical presentations. We present a unique case of congenital absence of right pulmonary artery (RPA) with left pulmonary artery (LPA) origin stenosis without any intracardiac or extracardiac lesion and its long-term follow-up.

Case summary

A 68-year-old woman underwent successful LPA stenting 23 years back for absent RPA and LPA origin stenosis. She was recently evaluated for breathlessness, almost two decades after the procedure. On evaluation, she was found to have severe pulmonary hypertension (Group 5) without any distortion of the LPA and with normally functioning stent.

Discussion

This report discusses the long-term outcome of stenting in the setting of severe stenosis of a single pulmonary artery. Over the years, the patient went on to develop severe segmental pulmonary hypertension (Group 5).

Intraoperative customized double-patch device with twin sutures for multiple muscular septal defects

OBJECTIVES

Closure of multiple muscular ventricular septal defects (VSDs) remains a challenge because of anatomical complexity.

METHODS

We mapped all the VSDs using en face reconstruction of the right ventricular septal surface through echocardiography and then performed an 'Intraoperative Customized Double-Patch Device' technique to surgically close them in 39 patients (male:female = 25:14). The median age of the patients was 6 months (2 months-10 years), and mean weight was 5.98 ± 4.21 kg. A patch of polytetrafluoroethylene was placed on the left ventricular side of the defect and another on the right ventricular side, and they were anchored to each other using 2 polypropylene sutures. Residual shunts were evaluated using intraoperative echocardiography and measurements of right atrial-pulmonary arterial saturation were taken in all patients.

RESULTS

The distribution of muscular VSDs was as follows: anterior muscular 12, posterior muscular 18, mid-muscular 11 and apical 9. The associated lesions included perimembranous VSD (n = 28), tetralogy of Fallot (n = 6), double-outlet right ventricle (n = 2) and supramitral membrane (n = 2). Mean clamp time and bypass time were 93 ± 19 min and 147 ± 26 min, respectively. Mean hospital stay was 11 ± 3.39 days with no in-hospital mortality. Five patients with significant residual shunts needed concomitant PA banding. All patients remained in New York Heart Association Class I. There was either no residual shunt (n = 3) or trivial shunt (n = 2) among the banded patients. All patients remained symptom-free and continued to thrive well at the most recent follow-up (3.48 ± 1.51 years).

CONCLUSIONS

Muscular VSDs can be mapped through en face reconstruction and closed using intraoperative customized double-patch device technique in a variety of situations with satisfactory immediate and short-term results.

Dual pathology causing severe pulmonary hypertension following surgical repair of total anomalous pulmonary venous connection: Successful outcome following serial transcatheter interventions

Surgical repair of total anomalous pulmonary venous connection (TAPVC) can be complicated by the development of pulmonary venous stenosis later on. In addition, the vertical vein, if left unligated, can remain patent and lead to hemodynamically significant left to right shunting. We report an infant who required transcatheter correction of both these problems after surgical repair of TAPVC.

Transposition of the Great Arteries With Total Anomalous Pulmonary Venous Connection

Transposition of the great arteries (TGA) with total anomalous pulmonary venous connection (TAPVC) is a rare association. Very few such cases have been reported. Among them 1 patient underwent anatomic repair. The rest received repair at the atrial level with either a modified Senning technique or a Mustard technique. We report a rare combination of TGA, TAPVC draining to the coronary sinus, and left juxtaposition of the atrial appendages with a diminutive right atrium. The anomalies were successfully repaired by anatomic correction.

Modified pediatric Bentall procedure: A novel technique in a rare case

Aneurysms of ascending aorta are rarely seen in pediatric age group. Only few cases with Marfans syndrome have been reported in the literature. Preferred treatment for these children has been the standard Bentall procedure (aortic root replacement with composite graft prosthesis). We report a 4-year-old male child with huge aneurysm of ascending aorta and aortic root dilation with severe aortic regurgitation, having phenotypic features of Loeys-Dietz syndrome type I. He underwent Bentall procedure with a novel modification (medial trap-door technique for coronary reimplantation). Short-term result of this procedure is encouraging and he is asymptomatic for the last 14 months of follow-up.

Transcatheter closure of large patent ductus arteriosus with severe pulmonary arterial hypertension: Short and intermediate term results

Objective:

To assess the efficacy and safety of transcatheter closure (TCC) of patent ductus arteriosus (PDA) with severe pulmonary arterial hypertension (PHT).

Background:

TCC of small and moderate-sized PDAs is well established. However, there is a paucity of data on TCC of large PDA with severe PHT.

Methods:

This is a retrospective observational study of 76 patients with large PDA and severe PHT who were referred for TCC. Multiple clinical and investigational parameters were evaluated to decide the reversibility of PHT. Following the TCC, patients were serially followed up to assess the efficacy and safety of closure and its impact on PHT.

Results:

Of 76 patients, nine were found to have PDA with Eisenmenger's syndrome. Of remaining 67, two were thought to have irreversible PHT based on hemodynamic data obtained after balloon occlusion of the duct. Sixty five patients, who eventually underwent TCC of PDA, had a median age of 9.1 years (range 1 month to 40 years). The weight ranged between 2.5 to 62 kg (median 14 kg). The PDA size was 9.1 ± 4.6 mm. The mean systolic pulmonary artery pressure was 66.9 ± 15.3 mm Hg. Duct occluder was used in 63 and muscular ventricular septal defect closure device in 2. The follow up was available in 56 (86%) with a mean follow up period of 65 ± 34 months. All the patients had complete closure of the PDA at 6 months follow up. Mild obstruction of left pulmonary artery (n=3) and aortic isthmus flow (n=6) was noted at the time of discharge. During the follow up, partial or complete resolution of PHT was observed in all the patients in whom Doppler-derived right ventricular systolic pressure was recorded (available in 40 of 56 patients).

Conclusions:

TCC of large PDA with severe PHT and significant left to right shunt was found to be effective and safe in the short and intermediate term.

Transcatheter closure of perimembranous ventricular septal defects using amplatzer asymmetric ventricular septal defect occluder: preliminary experience with 18-month follow up

BACKGROUND

This study reports our experience in the nonsurgical closure of perimembranous ventricular septal defects in children and adolescents with the Amplatzer asymmetric ventricular septal defect occluder and the outcome of an 18-month follow up.

METHODS AND RESULTS

Twenty patients (median age:10 years; median weight:32 kg) with perimembranous ventricular septal defect were selected for transcatheter closure with the Amplatzer device. The prosthesis diameter chosen was 1-2 mm larger than the largest measured diameter of the defect on transesophageal echo (TEE). All patients were put on oral aspirin (5 mg/kg/day in children and 150 mg/day in adults) five days prior to and for six months after closure. Follow-up evaluation at 48 hr and 1, 6, 12 and 18 months included clinical examination, electrocardiogram, and a transthoracic echocardiogram. The mean defect diameter on color flow mapping on TEE was 7.1 +/- 2.3 mm. The device diameter ranged from 6-14 mm (median = 8 mm). One patient developed an anaphylactic reaction to contrast. The procedure was successful in 17 out of 19 patients where it was attempted (89.4%). In two patients with associated significant aortic valve prolapse and mild aortic regurgitation the device could not be successfully deployed. A trivial residual shunt observed during postdeployment left ventricular angiogram in 7 of 17 patients (41.2%) completely disappeared at one month follow-up. Three patients had right bundle branch block (2 complete and 1 incomplete) whereas one developed junctional escape rhythm with a right bundle branch block morphology. One patient had clinically silent thromboembolism to the left vertebral artery and another patient had hemolysis which resolved spontaneously within 48 hr. Follow-up at 13.5 +/- 5.3 months (range 1-18 months) revealed no residual shunt. The left ventricular internal dimension in diastole decreased significantly from 45 +/- 6 mm to 40 +/- 6 mm (P < 0.01) at the time of the last follow up. The baseline tricuspid regurgitation (n = 4) and aortic regurgitation (n = 3) remained unchanged during the follow up period. None of the patients developed left ventricular outflow tract obstruction or new aortic or tricuspid regurgitation. There were no other device related complications such as device migration, systemic thromboembolism, infective endocarditis, pericardial effusion or delayed conduction disturbances.

CONCLUSIONS

In carefully selected children and young adults, the Amplatzer asymmetric ventricular septal defect occluder is a promising device for transcatheter closure of perimembranous ventricular septal defect with encouraging results on short term follow up.

Transcatheter closure of large secundum atrial septal defects using the 40 mm Amplatzer septal occluder: results of an international registry

Little is known about the efficacy and safety of the 40 mm Amplatzer septal occluder (ASO). Thirty-three patients (22 female, 11 male) with a large secundum atrial septal defect (ASD) underwent attempted device closure using the 40 mm ASO at a median age of 40 years (range, 14-81 years) and median weight of 65 kg (range, 48-98 kg). The median size of the ASD measured on 2D transesophageal echocardiography (27 patients) or intracardiac echocardiography (6 patients) was 30.5 mm (range, 24-39 mm) and the median balloon-stretched diameter was 37.7 mm (range, 32-43.7 mm). The median Qp:Qs ratio was 3.2:1 (range, 1.4-6.2). The attempt was unsuccessful in five patients; two had device embolization and one had left atrial wall perforation due to the sheath; all three required emergent surgery. The attempt was successful in the 28 remaining patients, resulting in complete immediate closure in 14 and a trivial residual shunt in 14. Fluoroscopy time ranged from 8.6 to 37.8 min (median, 12.2 min). At 24-hr follow-up, 2D transthoracic echocardiography with color flow Doppler revealed complete closure in 23 patients, and 5 had a trivial residual shunt. There were no complications encountered in patients who received the device. On follow-up, all patients are doing well. We conclude that the 40 mm ASO is safe and effective in most patients with a large ASD up to a diameter of 39 mm. However, the use of this device requires careful attention as the procedure may be unsuccessful or the device may embolize.

New technique for device closure of large atrial septal defects

The objective of this study was to describe a new technique for transcatheter device closure of large atrial septal defects (ASDs) using the Amplatzer septal occluder and our experience with this technique in 14 patients. Transcatheter closure of large (> 25 mm) ASDs is challenging. We have developed a balloon-assisted technique (BAT) to facilitate device closure of large ASDs. The BAT consists of using a balloon catheter to support the left atrial (LA) disk of the Amplatzer septal occluder during device deployment. The balloon support prevents prolapse of the LA disk into the right atrium. Between April 2003 and February 2004, 14 patients with large ASDs (mean age, 25.71 +/- 15.71 years; mean weight, 51.21 +/- 23.78 kg) underwent device closure with the Amplatzer septal occluder using the BAT. The median balloon-stretched diameter of the ASD was 32 (range, 26-40) mm. The median device size used was 33 mm (range, 26-40 mm). All 14 patients had successful deployment of the device using the BAT. The mean follow-up period was 16.5 +/- 11.95 weeks. No major complications were noted during the procedure or on short-term follow-up. The BAT enables predictably successful closure of large ASDs using the Amplatzer septal occluder.

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.

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.

Follow-up after coil closure of patent ductus arteriosus

A prospective serial follow-up after coil closure of patent ductus arteriosus in 84 patients showed a cumulative duct closure up to 96% at the end of 2 years. Five patients underwent transient recanalization, and 4 patients required repeat procedure for residual shunt or recanalization.

Emergent balloon mitral valvotomy in patients presenting with cardiac arrest, cardiogenic shock or refractory pulmonary edema

OBJECTIVES

The present study was performed to determine the outcome of emergent balloon mitral valvotomy (BMV) in patients with cardiac arrest, pulmonary edema or cardiogenic shock.

BACKGROUND

In India, many patients with mitral stenosis present in critical condition. They have high mortality despite surgical relief. The role of BMV in such patients is ill-defined.

METHODS

Of 558 patients undergoing BMV between January 1993 and December 1994, 40 presented with cardiogenic shock, cardiac arrest or pulmonary edema refractory to medical treatment and underwent emergent BMV (group I). Elective BMV was performed in the remaining 518 patients (group II).

RESULTS

Age ([mean +/- SD] 40 +/- 13 vs. 31 +/- 9 years, p < 0.05), incidence of atrial fibrillation (35% vs. 11%, p < 0.05), pulmonary artery systolic pressure (PAsP) (64 +/- 14 vs. 51 +/- 12 mm Hg, p < 0.001) and mitral valve (MV) score (7.4 +/- 1.2 vs. 6.4 +/- 1, p < 0.001) were higher and MV area lower (0.74 +/- 0.17 vs. 0.86 +/- 0.14 cm2, p < 0.001) in group I patients. After emergent BMV in group I, mitral regurgitation occurred in 15%, and the mortality rate was 35%. Stepwise logistic regression analysis identified MV score > or =8 (p = 0.008), PAsP > or =65 mm Hg (p = 0.023) and cardiac output < or =3.151 liters/min (p = 0.001) as significant predictors of a fatal outcome. Follow-up of 1 to 16 months (median 8) was available in 20 of 26 survivors in group I, of whom 15 were asymptomatic. The gain in MV area and the decrease in transmitral gradient and PAsP obtained immediately after BMV persisted during the follow-up period.

CONCLUSIONS

Emergent BMV is feasible in critically ill patients. In-hospital survivors have excellent clinical and hemodynamic status at intermediate follow-up.

Intraoperative radiofrequency microbipolar coagulation to replace incisions of maze III procedure for correcting atrial fibrillation in patients with rheumatic valvular disease

OBJECTIVE

Radiofrequency catheter ablation of atrial tachycardias and flutter is an established technique. The same modality in the microbipolar mode is effective in producing full thickness coagulation injury. Cox's maze procedure is highly successful in curing atrial fibrillation (AF) surgically. However, it consumes relatively long cross clamp time and cardiopulmonary bypass time. In this study, radiofrequency microbipolar coagulation was used as an adjunct to corrective valve surgery, as an intraoperative ablative modality to replace Cox's maze III incisions, thus remarkably shortening the procedure. The results of this procedure are compared historically with those of 26 patients who underwent corrective valve surgery alone.

METHODS

Radiofrequency microbipolar coagulation was used to produce conduction blocks along the Cox's maze III incision lines as an adjunct to valve surgery in 18 patients in atrial fibrillation undergoing surgery for rheumatic valvular disease. A bayonet type bipolar forceps with an active tip length of 7 mm drawing current from a microbipolar port of Valleylab Force 4 electrosurgical unit (Valleylab, Boulder, CO) was used for microbipolar coagulation. A 3-mm retinal handheld cryoprobe working on nitrous oxide gas was used for cryoablation.

RESULTS

A total of 15 survivors in the coagulation maze group were followed from 43 to 224 days (149.7 +/- 73.1 mean +/- S.D.). Twelve of the 15 survivors (80%) converted to normal sinus rhythm (70% confidence limit: 64.7-90.6%). Atrial transport function studies with pulsed wave doppler, showed presence of a wave in all the 12 (100%) patients in tricuspid valve flow and in nine (75%) patients in mitral valve flow. The procedure took 11.62 +/- 3.86 min of elective cardioplegic arrest time for the left atrial portion and 18.71 +/- 4.25 min of cardiopulmonary bypass time during reperfusion for the right atrial portion. Of the 23 survivors out of 26 patients who underwent the valve procedure alone, only one patient (4.3%) converted to normal sinus rhythm (70% confidence limit: 0.6-14%).

CONCLUSION

Thus, our modification considerably shortened the time taken for creating the maze in comparison to the Cox's maze procedure and was effective in restoring normal sinus rhythm in 80% of the patients.

Unusual tear in Inoue balloon during percutaneous balloon mitral valvuloplasty in a patient with calcific mitral stenosis

An unusual tear in an Inoue balloon during dilatation of calcific mitral stenosis is presented and its mechanisms discussed. An abnormal sequence of inflation indicates a possible tear.

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.

Thrombosed prosthetic valve in tricuspid position. Successful therapy with intravenous streptokinase

The successful use of streptokinase therapy in a child with chronic thrombosis of a prosthetic valve (Carbomedics) in the tricuspid position is presented.

Intracardiac needle in a man with self-injurious behaviour presenting with only a heart murmur

Symptoms of a heart murmur in a 48-year-old male schizophrenic patient with self-injurious behaviour were investigated. Immediately noticeable were multiple scars on his hands. Clinical evidence of subcutaneous needles and aortic regurgitation was found. Echocardiography revealed a linear metallic foreign body across the interventricular septum. He underwent surgery and via a right atriotomy, a needle from the same location was removed.

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.

Direct extension of bronchogenic carcinoma through pulmonary veins into the left atrium mimicking left atrial myxoma

Direct extention of bronchogenic carcinoma via pulmonary veins into the left atrium is rare. We describe two such cases, one which presented as a left atrial mass with pulmonary edema, and another which was detected at autopsy.

Streptokinase treatment of a thrombosed Björk-Shiley prosthesis in the aortic position

Dysfunction of a mechanical prosthetic valve caused by thrombus formation is usually treated surgically. A patient with a thrombosed Björk-Shiley valve in the aortic position was treated successfully with intravenous streptokinase. The considerable improvement in the patient's clinical condition and the phonocardiographic, echocardiographic, and cinefluoroscopic evidence of normalisation of prosthetic valve function established the efficacy of thrombolytic therapy of a thrombosed prosthetic valve in this patient.

Therapeutic guidelines for congenital complete heart block presenting in pregnancy

Congenital complete heart block presenting for the first time in pregnancy is a therapeutic challenge. Most of the reports are from an era when pacemaker therapy was in its infancy. Although isolated case reports have appeared, there are no definite guidelines for the management of such patients. We describe three cases of congenital complete heart block presenting in pregnancy. All the patients delivered normally with temporary pacing support during labor. Two of the three women remained symptomatic during the postpartum period when they were being weaned off the pacing support, so they were discharged with permanent pacemaker implantation. The third woman remained symptom-free during pregnancy, labor, and the postpartum period and was discharged without a permanent pacemaker; she is being followed with routine and 24-hour ambulatory electrocardiography. We review the literature in an attempt to formulate a therapeutic policy for such patients.

Long term results of percutaneous transluminal valvuloplasty in patients with valvular aortic stenosis

The results of percutaneous balloon aortic valvuloplasty (PBAV) in 62 consecutive patients with valvular aortic stenosis are reported. The age of the patients ranged from 11 months to 72 years (mean 28 +/- 12 years). Hemodynamically successful dilatation was achieved in 58 out of 62 patients. This was associated with marked clinical improvement in these patients. The left ventricular aortic peak to peak gradient decreased from 96.67 +/- 38.4 to 28.14 +/- 26.5mmHg (p < 0.01). There were no deaths during the procedure. Only one patient died in the hospital during the same admission. There was an increase in aortic regurgitation (AR) by at least one grade in 25 (40.3%) patients. Femoral arterial thrombosis was seen in 9/62 patients, 5 of them requiring surgical intervention. Follow up was available in 28 (45.1%) patients over a period of 2-15 months (mean 9 +/- 3 months). Two patients died during the follow up period. Doppler evaluation of gradients was done in all 28 patients with 15 consenting to undergo repeat cardiac catheterisation. Although hemodynamically the restenosis rate was 35.7% (10/28), only 2 of these patients showed symptomatic deterioration. The success of dilatation and restenosis rate were independent of the etiology of aortic stenosis, presence of calcification and the number of balloons used. This study demonstrates that PBAV is feasible in valvular aortic stenosis at low risk and is able to produce significant clinical and hemodynamic improvement in most cases with a restenosis rate of 35.7% at a follow up period of 9 +/- 3 months.

Unruptured congenital aneurysm of the left sinus of Valsalva presenting as acute right ventricular failure

A patient with unruptured congenital aneurysm of the left coronary sinus of Valsalva presented with acute right-sided heart failure due to right ventricular outflow tract obstruction. The mechanism for such an acute presentation may have been a sudden increase in the size of the aneurysm. The surgical importance of this lesion is the combined aortocameral approach which is seldom required for correction of such aneurysms.

MRI as guide to surgical approach in tuberculous pericardial abscess. Case report

In a 30-year-old man with tuberculous pericardial effusion and symptoms of constrictive pericarditis, 2-D echocardiography indicated localized effusion. Subsequent magnetic resonance imaging showed the effusion to be posterior and compressing the left ventricle. Guided by this information, pericardial resection with drainage of tuberculous abscess was performed via left anterior thoracotomy.

Pitfalls of subgroup analysis in randomized multicentre intervention trials

Results of randomized multicentre trials in patients with acute myocardial infarction form the basis of day-to-day therapy in intensive coronary care units all over the world. The results of subgroup analysis from these trials are applied by physicians to individual patients and hence, it is important to understand the limitations of subgroup analysis as performed in many of the trials. Performing multiple analyses increases the chance of making a type I error. Small sizes of subgroups increase the chance of a type II error. The use of univariate methods may show that patients with inferior wall infarction may not benefit from thrombolysis. A closer look may show that the number of patients with diabetes, hypertension, both or neither in the two subgroups are different, and the difference in response to thrombolysis may have been a reflection of this inequality rather than the site of infarction. TD minimize this fallacy we suggest an alternative strategy for subgroup analyses using prognostic scores which could assess cumulative risk of death resulting from the interactions of various risk factors for each patient. Comparison of subgroups with identical prognostic scores can rescue subgroup analysis from confounding bias ahd make it more meaningful. This could cut down the size and administrative costs incurred in conducting such multicentre intervention trials and also facilitate extrapolation of the results to individual patients.

Congenital intermittent atrio-ventricular dissociation in tetralogy of Fallot (a case report)

A case of tetralogy of fallot with congenital intermittent atrioventricular dissociation is reported. A review of standard postgraduate books of cardiology fails to describe this condition, thus showing its extreme rarity. The therapeutic dilemma in treating such a case is also discussed.

Acute myocardial infarction with normal coronary arteries in a case of polyarteritis nodosa: possible role of coronary artery spasm

A 20 year old man with no previous history of heart disease presented with acute left ventricular failure following extensive anterior wall myocardial infarction. Selective angiography revealed multiple aneurysms in the renal, mesenteric and hepatic arteries with an infarct in the lower pole of the right kidney. These findings, along with the presence of circulating hepatitis B surface antigen favoured the diagnosis of polyarteritis nodosa. In view of normal coronary angiogram and absence of myocardial vasculitis, coronary vasospasm was implicated as the cause of myocardial infarction. Such an occurrence, which could have different therapeutic and diagnostic implications, has not, to our knowledge, been previously described in polyarteritis nodosa.

Successful balloon valvotomy in isolated congenital tricuspid stenosis

Isolated congenital tricuspid valve stenosis is a rare entity. The modalities of definitive treatment have been surgical repair or replacement. We present the first reported patient with congenital tricuspid stenosis successfully treated by percutaneous balloon valvotomy. This appears to be an alternative to surgery when the anatomy, as demonstrated by echocardiography, is suitable.

Unusual case of pacemaker lead migration

Pulmonary artery migration of pacemaker lead is rare and may result in pulmonary emboli originating from the thrombus around the infected catheter and causing multiple pulmonary infarcts. We report an unusual case of pacemaker lead migration to the right pulmonary artery with septic pulmonary embolism. While being treated with intravenous Cefuroxamine, the patient had spontaneous migration of the lead to the left pulmonary artery with subsequent left pulmonary embolism.