PubMed Health⌕ Search

Biomedical subjects

A M Vora

Publications and source records attributed to A M Vora.

At least 19 recordsLinked to original sources
PubMed2002

Adenosine induced PR jump on surface ECG to differentiate atrioventricular nodal re-entrant tachycardia from concealed accessory pathway mediated tachycardia: a bedside test.

OBJECTIVE: To evaluate the efficacy of single dose intravenous adenosine in differentiating atrioventricular nodal re-entrant tachycardia (AVNRT) from concealed pathway mediated atrioventricular re-entrant tachycardia (AVRT) using surface ECG at the bedside. METHOD: 12 mg of adenosine was administered to 97 consecutive patients who had documented narrow QRS tachycardia without manifest pre-excitation. The test was labelled positive for AVNRT if surface ECG recordings showed signs of dual atrioventricular (AV) node physiology-namely, PR jump or AV nodal echo. The diagnostic value of this test was evaluated by electrophysiological study as the yardstick. RESULTS: The adenosine test was positive for AVNRT in 48 patients (adenosine induced PR jump in 48, AV nodal echo in 3) and negative in 49 patients. On electrophysiological study, 62 patients had AVNRT and 35 had concealed pathway mediated AVRT. Thus, the test had a sensitivity of 74% and specificity of 94%. The positive predictive value was 96% and the negative predictive value was 67%. CONCLUSION: Single dose (12 mg) intravenous adenosine administered during sinus rhythm can identify dual AV node physiology on surface ECG recording at the bedside. A positive adenosine test identified by a PR jump can differentiate AVNRT from AVRT with a high specificity and positive predictive accuracy.

Adenosine↗
PubMed2001

Restenosis after coronary stenting--incidence and predictors.

OBJECTIVE: To determine the intermediate term outcome after coronary artery stenting. METHODS: The six month angiographic and clinical follow-up of 92 consecutive patients (94 lesions) undergoing successful coronary stenting was performed. Multiple variables were analyzed for predicting restenosis. RESULT: The mean age was 49.7 +/- 8.5 years. There were 73 males and 19 females. Coronary artery involvement was left anterior descending artery (LAD) in 67%, left circumflex artery (LCx) in 16.5% and right coronary artery (RCA) in 16.5%. The pre-procedure mean reference diameter was 3.1 +/- 0.38 mm, minimal luminal diameter (MLD) was 0.47 +/- 0.28 mm and percentage diameter stenosis (DS) was 85 +/- 9%. Post procedure MLD improved to 3.1 +/- 0.4 mm with an acute gain of 2.6 +/- 0.4 mm and residual DS of only 3 +/- 3%. Clinical and angiographic variables were correlated with restenosis assessed as both binary and continuous variables. Angiographic follow-up could be obtained in 55 out of 92 patients (60%) and 86 patients (88%) had a clinical follow-up. Angiographic restenosis (> 50% diameter stenosis) was present in 12 (22%) patients, seven of whom required a repeat angioplasty procedure. There was no death. At follow-up, the MLD was 2.1 +/- 0.93 and the DS was 32 +/- 29% with a lumen loss of 0.92 +/- 0.84 mm. Only 14 (16%) of patients had angina and stress test was positive in 21 (23%). Hypercholesterolemia (p < 0.001) and female gender (p < 0.05) were independently associated with high lumen loss. CONCLUSION: Intracoronary stenting in an unselected patient group is associated with a 22% restenosis rate. Hypercholesterolemia and female gender are associated with higher restenosis.

Coronary Angiography↗
PubMed2000

Radiofrequency ablation: a cure for tachyarrhythmias.

Radiofrequency (RF) ablation is a new modality of pennanently curing patients with various tachycardias using radiofrequency energy, a technique evolved in the past decade. RF ablation was performed on 913 patients with different tachyarrhythmias from April, 1994 to July, 1999. There were 491 men and 422 females aged 42 +/- 34 years (range 1 to 76 years). Supraventricular tachycardia (SVT) was present in 462 patients, accessory pathway mediated atrioventricular re-entrant tachycardia (AVRT) in 355 patients (377 accessory pathways) and idiopathic ventricular tachycardia (VT) in 96 patients. Amongst the patients with SVT, 402 had atrioventricular nodal re-entrant tachycardia (AVNRT), 22 had atrial flutter, 20 had ectopic atrial tachycardia and 18 had atrial fibrillation. RF successfully abolished the tachycardia in 400/402 patients (99.5%) with AVNRT, 330/377 (87.5%) accessory pathways in patients with AVRT, 14/22 patients (63.6%) of atrial flutter, 18/20 patients (90%) of atrial tachycardia and 79/96 patients (82.3%) with idiopathicVT. Successful AV nodal ablation with pacemaker implantation was done in 10/18 patients with chronic atrial fibrillation with fast ventricular rate and tachycardia induced cardiomyopathy. AV nodal modulation for atrial fibrillation was tried in the remaining 8 patients and was successful in 4 (4/8). The overall success rate for all arrhythmias was 93.6%, and there was no mortality. At a follow-up of 6.8 +/- 5.4 months, there was a recurrence in 34/420 patients (8%), in whom successful re-ablation was performed. One patient with AVNRT and another with a parahisian pathway developed complete heart block and were given pacemakers. One patient developed inferior wall infarction on the next day post RF. There were 4 patients who had pericardial tamponade necessitating pericardiocentesis and 2 patients developed deep vein thrombosis, which was treated conservatively. Thus RF ablation is an effective, safe and curative therapy for various arrhythmias.

Adolescent↗
PubMed1999

Dual morphology of idiopathic ventricular tachycardia.

INTRODUCTION: Idiopathic ventricular tachycardia (VT) typically has a single morphology originating either in the right ventricular outflow tract (RVOT) or near the posterior fascicle of the left ventricle (LV) in most instances. We present our observations in six patients with idiopathic VT in whom two morphologies were present. METHODS AND RESULTS: Of 55 patients with idiopathic VT who underwent radiofrequency (RF) ablation, 44 had LV "fascicular" tachycardia, whereas 11 had RVOT tachycardia. During RF energy delivery, there was a change in VT morphology in two patients with idiopathic LV tachycardia. This second morphology was not ablated initially, recurred at follow-up, and was reablated successfully. In two additional patients with idiopathic LV tachycardia, a second VT was inducible after ablation of the "clinical" VT. This second morphology recurred at follow-up and was ablated successfully in one patient. The site where the second VT was ablated in all the three patients was remote from that of the first VT. In two patients with RVOT tachycardia, a second VT, originating from a different area of the RVOT, was induced after RF ablation of the "clinical" VT. This second VT recurred at follow-up and was reablated successfully in one patient. CONCLUSION: Idiopathic VT is a more heterogenous entity than hitherto believed. A second VT was seen in 11% of patients during or after RF ablation of the "clinical" VT. The appearance of a second VT suggests either a different exit site of the same circuit or another site of origin.

Adolescent↗
PubMed1999

Age at onset, gender distribution and intraarterial blood pressure changes in atrioventricular node-dependant tachycardias.

OBJECTIVE: Atrioventricular nodal reentrant tachycardia (AVNRT) and atrioventricular reentrant tachycardia (AVRT) utilising accessory pathways constitute the vast majority of paroxysmal supraventricular tachycardia (SVT). We studied the age at onset, the gender distribution and the intraarterial hemodynamics of these tachycardias. METHODS: The data of 224 patients who underwent electrophysiology study (EPS) and radiofrequency ablation was analysed. The age at onset of tachycardia was assessed by a careful history. The intraarterial BP was noted during sinus rhythm (SR), immediately after tachycardia onset (T0) and 15 seconds after the onset of tachycardia (T15). RESULTS: The age at onset of tachycardia was a decade later for AVNRT (48 +/- 10 years) than for AVRT (37 +/- 11 years). There was no gender preponderance in the AVNRT group (60 males, 56 females) while a male preponderance was seen in the AVRT group (71 males, 37 females, p < 0.01). There was a marked fall in the intraarterial systolic BP in both groups at the onset of tachycardia, from 143 +/- 24 mm Hg to 108 +/- 16 mm Hg (p < 0.05) for AVNRT and from 139 +/- 25 mm Hg to 107 +/- 18 mm Hg (p < 0.05) for AVRT. There was no correlation between the rate of tachycardia and the extent of fall of BP. CONCLUSION: Hospital-based data in an Indian setting found a similar pattern of age of onset of AV node-dependant tachycardia as in Western literature. However, unlike in Western studies, no female preponderance was seen in the AVNRT group. The fall in systolic BP at the onset of tachycardia is significant, similar in the two groups and independent of the rate of tachycardia.

Adult↗
PubMed1998

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.

Catheterization↗
PubMed1997

Atrioventricular nodal reentrant tachycardia with atrioventricular block.

Atrioventricular block (AVB) during atrioventricular nodal reentrant tachycardia (AVNRT) has been well documented, although it is not a common phenomenon. The mechanism for the initiation and resolution of AVB during AVNRT have been postulated. However, the site of AVB and its implication on the reentrant circuit in AVNRT is not clear. We illustrate two examples of AVNRT with AVB and offer further clarification on the site and mechanism of AVB.

Adult↗