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We present a digital system for adaptive data compression for low power wireless transmission of Electroencephalography (EEG) data. The proposed system acts as a base-band processor between the EEG analog-to-digital front-end and RF transceiver. It performs a real-time accuracy energy trade-off for multi-channel EEG signal transmission by controlling the volume of transmitted data. We propose a multi-core digital signal processor for on-chip processing of EEG signals, to detect signal information of each channel and perform real-time adaptive compression. Our analysis shows that the proposed approach can provide significant savings in transmitter power with minimal impact on the overall signal accuracy.

Study of U waves exemplifies important clinical role of noninvasive electrocardiography in modern cardiology. Present article highlights significance of U waves with a clinical case and also summarizes in brief the history of the same.

We describe a new technique of sealing cardiac perforation resulting in cardiac tamponade during transvenous mitral commissurotomy by percutaneous instillation of cyanoacrylate glue at the perforation site, thus avoiding surgery.

We report an unusual complication of a 25 mm long stent, which did not expand at all for 1 mm in its proximal segment, while rest of the 24 mm length of the stent got fully expanded. Repeated attempts to expand the extremely focal unexpanded part of the stent at high pressure led to rupture of the stent balloon and its entrapment. We failed to retrieve the balloon using various techniques and the patient had to be sent for coronary artery bypass graft surgery.

Alcohol septal ablation has recently been described as a safe alternative to surgical myectomy for treatment of symptomatic patients with hypertrophic obstructive cardiomyopathy. We describe a case where percutaneous myectomy was performed by mechanically occluding the septal artery using thrombogenic floppy tips of used PTCA wires instead of alcohol, as the anatomy of the septal artery was not suitable for alcohol ablation.

Background: Transcatheter closure of coronary artery fistulas has emerged as a successful alternative to surgery. We describe various techniques and short-term findings in 15 patients who were taken up for transcatheter closure of these fistulas., Methods and Results: Fifteen patients (aged 2-55 years; 12 males) with coronary artery fistulas underwent percutaneous transcatheter closure between June 1997 and December 2002. Site of origin of these fistulas were: right coronary artery in 7, left anterior descending coronary artery in 4, left main coronary artery in 2 and left circumflex coronary artery in 2 patients. Drainage site of these fistulas were: right ventricle in 9, right atrium in 4 and pulmonary artery in 2 patients. Out of these 15 fistulas, 14 were congenital and one was iatrogenically produced following inadvertent cutting balloon angioplasty of a septal perforator in a patient with chronic total occlusion of left anterior descending coronary artery. Various occlusion devices used to close these fistulas were: conventional metallic coils in 10, floppy tips of coronary angioplasty guidewires in 2, Amplatzer duct occluder in 1 and Amplatzer septal occluder in 2 patients. One of our patients had a coronary artery fistula draining by two openings into the right atrium, both of which were successfully closed using 2 Amplatzer duct occluders. Check angiogram after the procedure revealed complete occlusion in 13 (86.6%) and small residual flow in 2 patients. Follow-up studies at 3-55 months (mean 18 months) showed complete abolition of shunt in all patients with no evidence of recanalization leading to recurrence of shunt., Conclusion: Transcatheter closure of coronary artery fistulas is feasible and safe in the anatomically suitable vessels. Use of floppy tips of coronary angioplasty guidewires reduces the cost of the procedure significantly. which is an important consideration in developing countries like India.

Percutaneous transvenous mitral commissurotomy using Inoue balloon is an effective procedure for the management of patients with juvenile mitral stenosis. Inability to cross the mitral valve by the Inoue balloon catheter is one of the important reasons for failure of the procedure. We describe a new technique, facilitating left atrium to left ventricular entry using double loop of Inoue balloon catheter in a child with small left atrium.

We report the case of a female patient who presented with signs and symptoms of tricuspid stenosis. Echocardiography revealed a sessile mass on the tricuspid valve. A diagnosis of primary cardiac tumor was made but histopathologic examination revealed the mass to be an organized thrombus. Subsequent serological tests showed elevated titers of anticardiolipin antibodies in the absence of any associated disease. This case highlights an unusual presentation of the primary antiphospholipid syndrome.

Stenting is the treatment of choice for treating stenotic renal ostial lesions. During the stenting of an ostial lesion in a renal artery with post-stenotic dilatation, we were faced with the problems of unavailability of a balloon of appropriate length and diameter, and determining the real reference vessel diameter. The problem was solved by a simple technique.

Occlusion of a septal perforator branch alone, without the involvement of the left anterior descending coronary artery, leading to acute myocardial infarction is unusual. We report a case in which an isolated severely stenotic thrombus-containing first septal artery causing intractable post-myocardial infarction angina was successfully dilated and stented.

Successful transcatheter closure of a perimembranous ventricular septal defect with an Amplatzer device has been reported in patients with levocardia. We report a case in which the device could be deployed successfully in a child with isolated perimembranous ventricular septal defect with situs inversus and dextrocardia.

We report a case of coronary pulmonary arterial fistula that was successfully occluded by packing the fistula with thrombogenic floppy tips of used percutaneous transluminal coronary angioplasty guidewires instead of conventional steel coils., (Copyright 2003 Wiley-Liss, Inc.)

Chronic total occlusion of the left main coronary artery is very rare. We report a case in which a totally occluded, unprotected distal left main coronary artery was successfully revascularized percutaneously, establishing normal flow in the left main, left anterior descending and left circumflex coronary arteries.

We report a case in which a ruptured aneurysm of the sinus of Valsalva opening into the right atrium was successfully closed transcutaneously by an Amplatzer duct occluder.

Pseudoaneurysm following diagnostic or interventional procedures is a well-known complication. We describe a new method of closing a femoral pseudoaneurysm in a case where ultrasound-guided compression had failed. Instead of packing the sac permanently with coils, thrombus formation was successfully induced by temporary placement of a coil transcutaneously in the psendoaneurysm sac, which resulted in closure of the pseudoaneurysm.

A cardiac hydatid cyst is rare. We report a case of cardiac hydatid cyst localized in the atria which was diagnosed by two-dimensional echocardiography following a thromboembolic stroke. Surgical resection of the cyst was performed and histopathologic examination confirmed the diagnosis.