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A 66-year-old diabetic, hypertensive, and hypothyroid female presented in the emergency department with cardiac arrest, for which cardiopulmonary resuscitation was immediately initiated. She had been on oral fexofenadine for 36 h prior to the event. Post successful resuscitation, her cardiac rhythm showed high-grade atrioventricular block. Patient was treated with mechanical ventilatory support and temporary transvenous pacing. No treatable cause could be identified, and she recovered completely following fexofenadine discontinuation, without need for a permanent pacemaker. She has remained asymptomatic during 1 year of follow-up with no documented arrhythmias. An electrophysiological study at 6 months revealed prolonged HV interval (70 ms) with 1:1 AV conduction and no inducible arrhythmias. This is probably the first reported case of fexofenadine-induced cardiac arrest in a patient without previous history of heart disease.

Sudden death is one of the more frequent causes of death for hemodialysis patients, but the underlying mechanisms, contribution of arrhythmia, and associations with serum chemistries or the dialysis procedure are incompletely understood. To study this, implantable loop recorders were utilized for continuous cardiac rhythm monitoring to detect clinically significant arrhythmias including sustained ventricular tachycardia, bradycardia, asystole, or symptomatic arrhythmias in hemodialysis patients over six months. Serum chemistries were tested pre- and post-dialysis at least weekly. Dialysis procedure data were collected at every session. Associations with clinically significant arrhythmias were assessed using negative binomial regression modeling. Sixty-six patients were implanted and 1678 events were recorded in 44 patients. The majority were bradycardias (1461), with 14 episodes of asystole and only one of sustained ventricular tachycardia. Atrial fibrillation, although not defined as clinically significant arrhythmias, was detected in 41% of patients. With thrice-weekly dialysis, the rate was highest during the first dialysis session of the week and was increased during the last 12 hours of each inter-dialytic interval, particularly the long interval. Among serum and dialytic parameters, only higher pre-dialysis serum sodium and dialysate calcium over 2.5 mEq/L were independently associated with clinically significant arrhythmias. Thus, clinically significant arrhythmias are common in hemodialysis patients, and bradycardia and asystole rather than ventricular tachycardia may be key causes of sudden death in hemodialysis patients. Associations with the temporal pattern of dialysis suggest that modification of current dialysis practices could reduce the incidence of sudden death.

Background Fractional Flow Reserve (FFR), a measure of coronary stenosis severity is based on the achievement of maximal hyperemia of coronary microcirculation. The most widely used pharmacological agent is adenosine which is administered either by intra coronary or intra venous routes. IV route is time consuming, has more side effects and expensive. This study is undertaken to compare the two routes of administration. Methods FFR was assessed in 50 patients with 56 intermediate focal lesions using both IV and intracoronary (IC) adenosine. FFR was calculated as the ratio of the distal coronary pressure to the aortic pressure at maximal hyperemia. Results A total of 25 left anterior descending, 8 right, 21 circumflex, and 2 left main coronary arteries were evaluated. The mean percent stenosis was 63.91 ± 13.13 SD and, the mean FFR was 0.831 ± 0.0738 SD for IV and 0.832 ± 0.0707 SD for IC adenosine. There was a strong and linear correlation between 2 sets of observations with IV dose and IC adenosine dose ( R = 0.964, y = 0.065 + 0.923 x ; p y = IV dose, x = IC dose). The agreement between the two sets of measurements was also high, with a mean difference of: 0.001 ± 0.0197. The changes in heart rate and blood pressure were significantly higher in IV adenosine group. Different incremental doses were well tolerated, with fewer systemic adverse events with IC adenosine. Transient AV blocks were observed with both IV and IC adenosine. Conclusions This study suggests that IC adenosine is equivalent to IV infusion for the determination of FFR. The administration of IC adenosine is easy to use, cost effective, safe and associated with fewer systemic events.

Patient initials or identifier number STU ### Relevant clinical history and physical exam ### Relevant test results prior to catheterization ### Relevant catheterization findings ![Figure][1] ### Procedural step CAG was done. Wired the lesionwith Whisper ES wire and Floppy wire in

Abciximab (a glycoprotein IIb/IIIa inhibitor) was assessed in 16 of 36 patients with acute myocardial infarction who were referred for rescue angioplasty after failed thrombolysis. Baseline clinical and angiographic characteristics were comparable in the abciximab and non-abciximab groups. Coronary stenting was carried out in all patients in the non-abciximab group and in 13 in the abciximab group. Angiographic success was achieved in all patients. Persistence of slow flow was encountered more frequently in the non-abciximab group (30% versus 6.25%, p < 0.05). Stent thrombosis occurred in 2 patients (10%) who were successfully redilated and there was one case of bleeding requiring transfusion in the non-abciximab group; neither of these complications occurred in the abciximab group. Predischarge left ventricular ejection fraction was better in the abciximab group (44% ± 3% versus 36% ± 3%, p < 0.01). All patients were discharged alive and were asymptomatic at the one-month follow-up. Use of abciximab during angioplasty after failed thrombolysis improved angiographic and clinical results without increasing the risk of bleeding, and reduced the incidence of in-hospital complications. Larger studies are warranted to confirm this important observation.

Surgical transmyocardial laser revascularization has been reported to improve clinical outcome in patients with refractory angina who are not candidates for angioplasty or bypass surgery. We investigated the feasibility and safety of a nonsurgical, percutaneous technique for laser channel creation using energy from a holmium:yttrium-aluminium-garnet (YAG) laser. The laser energy was directed through a fiber enclosed in a catheter to the ventricular myocardium creating channels between the blood pool and the myocardium. Thirty-five patients with angina and coronary anatomy not amenable to revascularization with coronary angioplasty or bypass surgery underwent percutaneous transluminal myocardial revascularization. A total of 15 +/- 5 channels were formed per patient. There was no procedure-related mortality. One patient developed cardiac tamponade requiring thoracotomy and another a minor self-limiting pericardial effusion. There was no worsening of regional wall motion function in any patient. All patients were discharged alive after a postprocedure hospital stay of 2.1 +/- 1.4 days. Mean Canadian Cardiovascular Society (CCS) functional class declined from 3.68 +/- 0.4 before procedure to 0.82 +/- 0.7 at 30 days (P < 0.01). At 3 months, mean angina class was 0.94 +/- 0.65 (n = 35; P < 0.01) and at 6 months, mean angina class was 1.08 +/- 0.58 (n = 26; P < 0.01). One patient required repeat revascularization after 5 months for progression of disease in a degenerated saphenous venous graft supplying different region of myocardium. We conclude that transmyocardial revascularization using holmium:YAG laser by percutaneous technique can be carried out safely with encouraging early results and a very low complication rate. The symptomatic relief seen up to 6 months has been excellent. The long-term effects of this technique on mortality and relief of angina, however, remain to be defined. Cathet. Cardiovasc. Intervent. 47:287-291, 1999.

Absorb Bioresorbable Vascular Scaffold (BVS) is a relatively new device in the management of coronary artery disease. Initially, Bioresorbable Vascular Scaffold (BVS) was studied in chronic stable lesions. There is emerging data on its usage in acute coronary syndrome (ACS) lesion. The manufacturer

To compare the second generation drug eluting stent (DES) (XIENCE PRIME) with new second generation DES (XIENCE PRO) having lower everolimus content in acute coronary syndromes (ACS) patients. All patients of acute coronary syndromes undergoing second generation DES implantation at our center

GENAMI, an angiographic follow-up study was undertaken to evaluate the safety and efficacy of a new generation endothelial progenitor cell (EPC) capture stent, GENOUS during primary angioplasty for ST-elevation myocardial infarction (MI).Eleven consecutive patients with acute ST-elevation MI underwent primary percutaneous coronary intervention (PCI) using a bio-engineered GENOUS EPC stent.Procedural success was 100%. Ten patients who survived underwent a follow-up angiography at 8 months. There was no instance of stent thrombosis during the follow-up period up to 12 months. The quantitative angiographic (quantitative coronary analysis [QCA]) follow-up data showed a late loss at 8 months of 0.97 +/- 0.94 mm and the late loss index was 44.35 +/- 40.47% with angiographic restenosis seen in 5 of 10 patients (50%). One of these patients with provocable ischemia underwent repeat PCI.The QCA data of this study shows a high late loss with frequent angiographic restenosis during follow-up with this stent during primary PCI for acute STEMI. This observation, with important clinical implications, needs to be confirmed in larger studies.

Mahaim pathways are characterized by the presence of an accessory pathway potential-the 'M' potential, at the tricuspid annulus. M potential is a very useful guide during radiofrequency ablation of Mahaim pathway. During ablation, an accelerated rhythm with ORS morphology, identical to fully pre-excited QRS complex is observed, and has been labeled as Mahaim automatic rhythm. We analyzed this rhythm during radiofrequency ablation of these pathways.Eighteen patients with Mahaim accessory pathways were taken up for electrophysiology study and radiofrequency ablation. Tricuspid annulus was mapped for 'M' potentials and targeted for ablation. Duration of ablation and number of ablation attempts were guided by Mahaim automatic rhythm during ablation. Mahaim tachycardia was inducible in all. 'M' potentials were recorded in 15/18 patients. Radiofrequency energy was delivered at the site where Mahaim accelerated rhythm was noticed and was continued till abolition of the rhythm. This resulted in long-term success. In 3 patients, M potentials were not recordable, and in them other methods including 3-dimensional electroanatomical mapping was also not successful.'M' potential-guided radiofrequency ablation is a useful technique. Presence of Mahaim automatic rhythm and its abolition during ablation is associated with long-term success of the procedure.

Of the various therapeutic modalities available to treat ectopic atrial tachycardia, radiofrequency catheter ablation has shown excellent results. It is usually possible to localize the earliest site of endocardial activation by conventional or newer three-dimensional mapping techniques. We report a case of ectopic atrial tachycardia, wherein the tachycardia was being repeatedly interrupted by mechanical trauma. Finally, with the help of P wave pace mapping, the tachycardia was localized near the posterolateral part of the mitral annulus, and successfully ablated. This report demonstrates the utility of P wave pace mapping in ectopic atrial tachycardia.

Coronary sinus electrograms generally represent the sequence of left atrial activation, and are very helpful in localizing and differentiating left lateral accessory pathway-mediated tachycardia from other supraventricular tachycardias. The activation of the coronary sinus from the left atrium occurs through muscle bridges, which may be discrete or form an intermingled continuum. These muscle bridges, if disconnected, may dissociate the coronary sinus from the left atrium, in which case the coronary sinus electrograms do not represent left atrial activation, and do not help to understand, or may cause misinterpretation of, the mechanism of supraventricular tachycardia. We report one such case of orthodromic supraventricular tachycardia mediated through the left lateral accessory pathway in which the coronary sinus got dissociated from the left atrium during radiofrequency ablation.

BACKGROUND: Slow flow or no reflow phenomenon is increasingly being recognized as a serious problem during coronary angioplasty and stenting. This phenomenon is seen more often during angioplasty in highly thrombogenic milieux, especially in a setting of acute myocardial infarction. The treatment of this complication is often not satisfactory. In this study the authors assessed the efficacy of abciximab, a potent antiplatelet drug, in treating slow flow or no reflow phenomenon during primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI). METHODS: Twenty-one instances of persistent slow flow phenomenon were encountered in 131 consecutive patients subjected to primary PTCA for AMI (16%). It was more common in patients presenting with AMI complicated by cardiogenic shock (nine of 21, 43%). Of these 21 cases of slow flow, 10 patients were given injection abciximab during the procedure of primary PTCA as a bail-out measure after encountering the complication of slow flow or no reflow. A pre-discharge coronary angiography was carried out in all patients who survived. RESULTS: In seven of 10 patients in the abciximab group flow had improved to TIMI-3. In contrast, in the non-abciximab group TIMI flow improved in only four of 11 patients. Patients with persistent slow flow had significantly higher mortality at the first 30-day follow-up than patients with TIMI-3 flow (33% versus 1.8%, p0.001). CONCLUSION: In this small nonrandomized study significant improvement in coronary flow was achieved by using intravenous abciximab after observing slow flow or no reflow phenomenon during primary PTCA. More frequent use of this drug in this milieu might help in preventing the development of this complication. Larger studies are warranted to confirm this life-saving beneficial effect of bail-out administration of abciximab during primary angioplasty.

The results of primary coronary stenting for acute myocardial infarction (AMI) have been reported to improve significantly with the concomitant administration of platelet glycoprotein IIb/IIIa inhibitor abciximab. There are, however, no data available with the use of eptifibatide, a more cost-effective, small-molecule GP IIb/IIIa blocker with a shorter half-life. In a prospective multicenter feasibility and efficacy study, we assigned 55 consecutive patients with AMI being taken up for primary stenting to receive eptifibatide just before the procedure (two boluses of 180 μg/kg 10 min apart and a 24-hr infusion of 2 μg/kg/min). Clinical outcomes were evaluated at 30 days after the procedure. The angiographic patency of the vessel with TIMI flow rates, TIMI myocardial perfusion (TMP) grade, and corrected TIMI frame counts were assessed at the end of procedure and before hospital discharge. At 30 days, the primary endpoint, a composite of death, myocardial infarction, and urgent target vessel revascularization (TVR) was seen in 12.7% of patients. The TIMI 3 and TMP grade 3 flow, which was seen in 93% and 86% of patient, respectively, at the end of the procedure, declined to 86% and 78%, respectively (P < 0.05) before hospital discharge. Corrected TIMI frame counts also decreased from 25.7 ± 7.2 to 22.9 ± 6.8 (P < 0.05). There were five (9.1%) instances of subacute thrombosis (SAT) presenting as AMI, needing urgent TVR in all, within 3–5 days of the primary procedure. No excessive bleeding complication, directly attributable to the use of eptifibatide, was observed. The study was terminated prematurely because of an unacceptable SAT rate. Administration of eptifibatide along with primary stenting for AMI is associated with a high TIMI 3 and TMP grade 3 flow acutely. However, these flows decline significantly before hospital discharge and lead to a high rate of SAT. The dosage and duration of infusion of eptifibatide in this setting needs further evaluation. Cathet Cardiovasc Intervent 2002;57:497–503. © 2002 Wiley-Liss, Inc.

Primary pulmonary hypertension is a rare disorder of unknown etiology with a poor prognosis. There is no cure, and drug therapy is effective in only a few patients. Calcium-channel antagonists and anticoagulants are the mainstay of therapy. Prostacyclin therapy leads to significant clinical improvement but its use is restricted due to high cost and complex drug delivery systems. Sildenafil is a selective vasodilator and has been shown to be effective in decreasing pulmonary vascular resistance in animal models of pulmonary hypertension. We report the use of sildenafil in two patients of primary pulmonary hypertension who were refractory to conventional drug therapy.

Primary coronary stenting is being increasingly used in patients undergoing primary coronary angioplasty for acute myocardial infarction. In this prospective study we evaluated our experience of direct angioplasty in 68 patients with acute myocardial infarction of whom 57 received intracoronary stents using high-pressure deployment (> or =12 atmospheres) with adjunct aspirin and ticlopidine therapy without coumadin. All patients underwent pre-discharge follow-up angiography. Stent implantation was successful in all patients. Stent thrombosis was not seen in any patient. However, TIMI grade 3 flow was obtained in only 51 patients (89.6%) with evidence of slow flow present in remaining six patients. Follow-up angiograms showed no stent thrombosis but five out of the six patients (83%) with slow-flow phenomenon persisted to have slow flow. These patients had lower left ventricular ejection fraction as compared to patients with TIMI 3 flow at follow-up angiography (27.5 +/- 10.2% vs. 42.1 +/- 15.2%, P < .001) and a high mortality (two out of six) within 30 days. Primary stenting is safe and feasible in the majority of patients with good short-term outcomes, but persistent slow-flow phenomenon with adverse clinical outcome is seen in a small but significant number of patients.

Percutaneous coronary intervention (PCI) of the infarct related artery(IRA) during primary PCI for ST elevation myocardial infarction (STEMI) is appropriate. Two retrospective analyses suggested that, direct PCI to the IRA without knowledge of the anatomy of the contra lateral artery is feasible .