Narayanan Namboodiri

Electrophysiological features of atrial flutter in cardiac sarcoidosis: a report of two cases.

We report two cases of systemic sarcoidosis with atrial flutter as the clinical manifestation. In one patient, who had symptoms of shorter duration, the arrhythmia was no longer inducible after a course of glucocorticoid therapy. Electroanatomical mapping in the other case revealed patchy fibrosis of the left atrial myocardium and multiple macro-reentrant circuits. Sinus rhythm could be restored with ablation of these reentrant circuits. To our knowledge, this is the first report on the demonstration of atrial scarring in a patient with sarcoidosis using 3-D electroanatomical mapping. These two cases illustrate that the inflammation of atrial myocardium is the primary mechanism of atrial arrhythmias in patients with cardiac sarcoidosis.

Percutaneous closure of ruptured sinus of Valsalva aneurysms: intermediate term follow-up results.

Aims: Surgical repair used to be the conventional treatment of ruptured sinus of Valsalva aneurysms (RSOVA). Recently many articles have described the percutaneous closure of these defects. We report the successful percutaneous closure of seven cases of RSOVA. Methods and results: All the procedures were done under local anaesthesia with fluoroscopic and echocardiographic guidance. The defects were closed with nitinol ductal occluders introduced from the venous side after the establishment of an arteriovenous loop. Of the seven patients (four males, mean age 44.8±11 years), six had rupture of the congenital sinus of Valsalva aneurysm, and one had a recurrence following surgical repair. Out of the six patients with aneurysms of the right aortic sinus, four had rupture into the right atrium, one into the right ventricular (RV) inflow and the other into RV outflow. One patient had non-coronary sinus aneurysm rupturing into the right atrium. The size of the distal opening of the aneurysm varied from 2.5 to 12 mm. The left to right shunt flow ratio (Qp/Qs) ranged from 1.5 to 3.6. The size of the nitinol ductal occluders used to close the defects varied from 4 to 16 mm. After a mean follow-up period of 9.3±3 months, all patients remained asymptomatic with no residual flow, aortic valvar insufficiency, or evidence of infection. Conclusions: RSOVAs can be safely and effectively closed percutaneously using nitinol ductal occluders.

Subannular left ventricular pseudoaneurysm following mitral valve replacement

Delayed development of left ventricular pseudoaneurysm is a rare late complication of mitral valve prosthesis and requires early surgical intervention. Here we describe the occurrence of such a complication diagnosed 6-months after the valve surgery in a 60-year-old lady. The anatomic delineation of subannular left ventricular pseudoaneurysm using multiple imaging modalities including CT angiography is also being discussed.

Tako-tsubo cardiomyopathy in a patient with myasthenia gravis crisis: a rare clinical association.

Tako-tsubo cardiomyopathy (TTC) is increasingly being recognised as transient left ventricular dysfunction following various hyperadrenergic states such as emotional or physical stressors. The association of this rare clinical entity with myasthenia gravis (MG) has been reported only twice in the literature, both following plasmapheresis for MG crisis. Here we describe a unique case of TTC in a 40-year-old woman with MG admitted with MG crisis managed conservatively. This case suggests that plasmapheresis is unlikely to have a causative role in the development of TTC in these patients. Patients with MG crisis may be at potential risk of developing TTC and careful clinical and electrocardiographic monitoring is necessary while treating them. The possible role of stress as the common precipitating factor in both conditions is also discussed.

Doppler echocardiographic assessment of TTK Chitra prosthetic heart valve in the mitral position

AIMS TTK Chitra heart valve prosthesis (CHVP), a tilting disc mechanical heart valve of low cost and proven efficacy, has been in use for the last 15 years. Although various studies substantiating its long-term safety and efficacy are available, no study had assessed its echocardiographic characteristics. The purpose of this study was to determine the normal Doppler parameters of CHVP in the mitral position and to assess whether derivation of mitral valve area (MVA) using the continuity equation (CE) and more commonly used pressure half-time (PHT) method is comparable in the functional assessment of this tilting disc mitral prosthesis. METHODS AND RESULTS Doppler echocardiography was performed in 40 consecutive patients with CHVP in the mitral position. All patients were clinically stable, without evidence of prosthetic valve dysfunction such as significant obstruction or regurgitation, endocarditis, left ventricular dysfunction (ejection fraction <40%), or significant aortic regurgitation. Valve sizes studied included 25, 27, and 29 mm. Mitral valve area was derived both by the PHT method and by the CE, using the stroke volume measured in the ventricular outflow tract divided by the time-velocity integral of CHVP jet. The peak Doppler gradient ranged from 5 to 21 (mean 11.0) mmHg, and the mean gradient ranged from 1.7 to 9.2 (mean 4.1) mmHg. Mean gradient negatively correlated with an increase in the actual orifice area (AOA) derived from the valve orifice diameter given by the manufacturer (r = -0.45, P = 0.004). Mitral valve area calculated by both PHT and CE increased significantly with an increase in the AOA (r = 0.42, P = 0.007 and r = 0.32, P = 0.046, respectively). Mitral valve area by the CE averaged 1.55 +/- 0.36 cm(2) (range 0.85 cm(2) for a 25 mm valve to 2.41 cm(2) for a 29 mm valve) and was smaller than by PHT (mean 2.04 +/- 0.41 cm(2), range 1.40-3.14 cm(2); P = 0.0001; t-test), irrespective of whether PHT is less than or >110 ms. CONCLUSION The Doppler parameters obtained with CHVP in the mitral position are comparable with those obtained with the different prosthetic valves in common use. In the selected group of patients with CHVP, assessment of MVA by the PHT method is comparable with that by the CE. Areas by both methods were smaller than the AOA provided by the manufacturer, as seen in other similar design valves.

KCNQ1 mutations associated with Jervell and Lange–Nielsen syndrome and autosomal recessive Romano–Ward syndrome in India—expanding the spectrum of long QT syndrome type 1

Long QT syndrome type 1 (LQT1) is the most common type of all Long QT syndromes (LQTS) and occurs due to mutations in KCNQ1. Biallelic mutations with deafness is called Jervell and Lange–Nielsen syndrome (JLNS) and without deafness is autosomal recessive Romano–Ward syndrome (AR RWS). In this prospective study, we report biallelic mutations in KCNQ1 in Indian patients with LQT1 syndrome. Forty patients with a clinical diagnosis of LQT1 syndrome were referred for molecular testing. Of these, 18 were excluded from the analysis as they did not fulfill the inclusion criteria of broad T wave ECG pattern of the study. Direct sequencing of KCNQ1 was performed in 22 unrelated probands, parents and at‐risk family members. Mutations were identified in 17 patients, of which seven had heterozygous mutations and were excluded in this analysis. Biallelic mutations were identified in 10 patients. Five of 10 patients did not have deafness and were categorized as AR RWS, the rest being JLNS. Eight mutations identified in this study have not been reported in the literature and predicted to be pathogenic by in silico analysis. We hypothesize that the homozygous biallelic mutations identified in 67% of families was due to endogamous marriages in the absence of consanguinity. This study presents biallelic gene mutations in KCNQ1 in Asian Indian patients with AR JLNS and RWS. It adds to the scant worldwide literature of mutation studies in AR RWS.

Persistent pulmonary artery hypertension in patients undergoing balloon mitral valvotomy.

Pulmonary artery pressure (PAP) is known to regress after successful balloon mitral valvotomy (BMV). Data of persistent pulmonary artery hypertension (PPAH) following BMV is scarce. We analyzed the clinical, echocardiographic, and hemodynamic data of 701 consecutive patients who have undergone successful BMV in our institute from 1997 to 2003. Data of 287 patients who had PPAH (defined by pulmonary artery systolic pressure [PASP] of ≥ 40 mmHg at one year following BMV) were compared to the data of 414 patients who did not have PPAH. Patients who had PPAH were older (39.9 ± 9.9 years vs. 29.4 ± 10.1; P < 0.001). They had higher prevalence of atrial fibrillation (AF; 21.9 vs. 12.1%, P < 0.05), moderate or severe pulmonary artery hypertension (PAH) defined as PASP more than 50 mmHg (43.5 vs. 33.8%, P = 0.00), anatomically advanced mitral valve disease as assessed by Wilkins echocardiographic score > 8 (33.7 vs. 23.2%, P < 0.001), and coexistent aortic valve disease (45.6 vs. 37.9%, P < 0.001) at the baseline. Those patients with PPAH had comparatively lower immediate postprocedural mitral valve area (MVA). On follow-up of more than five years, the occurrence of restenosis (39.3 vs. 10.1%, P = 0.000), new onset heart failure (14% vs. 4%, P < 0.05) and need for reinterventions (9.5% vs. 2.8%, P < 0.05) were higher in the PPAH group. Patients with PPAH were older, sicker, and had advanced rheumatic mitral valve disease. They had higher incidence of restenosis, new onset heart failure, and need for reinterventions on long term follow-up. PPAH represents an advanced stage of rheumatic valve disease and indicates chronicity of the disease, which may be the reason for the poorer prognosis of these patients. Patients with PPAH requires intense and more frequent follow-up.

Immediate and Long-term Results Following Balloon Mitral Valvotomy in Patients With Atrial Fibrillation

The purpose of this study was to examine the influence of atrial fibrillation (AF) on the immediate and long‐term outcome of patients undergoing balloon mitral valvotomy (BMV).

Ventricular septal rupture following myocardial infarction. Long-term survival of patients who did not undergo surgery. Single-centre experience.

Long-term survival is rare in patients not undergoing surgery after post-myocardial infarction ventricular septal rupture.We report our experience of seven patients out of 27, who did not undergo surgery and were followed up for a mean period of 2.8 years.They were evaluated after a mean period of 2.2 months after infarction in our centre. The septal defects measured 9.8 mms on average and the mean left-to-right shunt ratio was 1.98:1. The mean pulmonary artery, right atrial and left ventricular end diastolic pressures were 28.3 ± 10.6, 4 ± 3 and 15.8 ± 4.8 mm Hg, respectively. Only three out of seven patients had LV aneurysm and all patients had single-vessel disease. Smaller defect size, minimal left-to-right shunt and preserved right ventricular function may be the factors responsible for long-term survival.

Narrow complex tachycardia with ventriculoatrial dissociation--what is the mechanism?

Case Presentation A 38-year-old woman presented with recurrent sustained episodes of palpitation, each episode lasting more than 3 weeks. The symptoms were unresponsive to amiodarone 400 mg/day. Echocardiogram revealed mildly dilated left ventricle with global left ventricular hypokinesia and ejection fraction of 30%. The electrocardiogram (ECG) during palpitation showed a narrow QRS tachycardia with ventriculoatrial (VA) dissociation and mild variations in RR interval (Fig. 1A). The QRS complex during the tachycardia was relatively narrow (100 ms), and exhibited left anterior fascicular (LAF) block morphology and leftward (−45◦) axis. During sinus rhythm, ECG was unremarkable, except for mildly prolonged QTc (480 ms) (Fig. 1B). Baseline electrophysiology study showed sinus rhythm (cycle length 700 ms), normal atrial-His (AH; 76 ms) and His-ventricular (HV; 48 ms) intervals, and absence of VA conduction on pacing from right ventricular (RV) apex at 600 ms. Programmed atrial stimulation showed no dual atrioventricular (AV) nodal physiology. Atrial and ventricular burst and extrastimulation pacing induced the clinical tachycardia easily and reproducibly (Fig. 2A). During the tachycardia (cycle length around 370 ms, HV interval +6 ms), His Bundle (HB) and right bundle (RB) were activated sequentially with a HB-RB interval of 20 ms, which was similar to the HB-RB interval measured during sinus rhythm. Rapid pacing from the RV apex and basal RV septum at cycle length of 360 ms, during the tachycardia, resulted in constant fusion beats, with postpacing intervals exceeding the tachycardia cycle lengths by 154 and 76 ms, respectively. Intravenous bolus of adenosine 18 mg did not affect the