Late lumen loss and intima hyperplasia after sirolimus-eluting and zotarolimus-eluting stent implantation in diabetic patients: the diabetes and drug-eluting stent (DiabeDES III) angiography and intravascular ultrasound trial.

AIMS: Patients with diabetes mellitus have increased risk of in-stent restenosis after coronary stent implantation due to neointimal hyperplasia (NIH). The aim of this study was to use quantitative coronary angiography (QCA) and volumetric intravascular ultrasound (IVUS) to evaluate the effects of the sirolimus-eluting Cypher® stent (SES) and the zotarolimus-eluting Endeavor® stent (ZES) on angiographic late lumen loss and intima hyperplasia in diabetic patients. METHODS AND RESULTS: In the DiabeDES III trial, 127 patients were randomised to SES or ZES stent implantation. Angiographic 10-month follow-up data were available in 105 patients, including 48 SES and 57 ZES treated patients. Angiographic endpoints were in-stent late lumen loss and minimal lumen diameter. IVUS endpoints included NIH volume and in-stent percent volume obstruction. Baseline clinical characteristics and lesion parameters were similar in the two groups. At 10-month follow-up, angiographic in-stent late lumen loss (0.14±0.37 mm vs. 0.74±0.45 mm, p<0.001) was reduced and minimum lumen diameter was higher (2.36±0.53 mm vs. 1.96±0.65, p<0.001) in the SES group as compared to the ZES group. As compared to the ZES group, NIH volume was significantly reduced in the SES group (median [interquartile range]: 0.0 mm3 [0.0 to 1.2] vs. 16.5 mm3 [6.2 to 31.1], p<0.001). In-stent% volume obstruction was significantly reduced in SES as compared to ZES (median [interquartile range]: 0.0% [0.0-0.7] vs. 13.0% [6.7-20.8], p<0.001). CONCLUSIONS: In diabetic patients, the SES reduced angiographic late lumen loss and inhibited NIH more effectively than ZES.

A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome.

AIMS: In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any difference between single-lead atrial pacing (AAIR) and dual-chamber pacing (DDDR). METHODS AND RESULTS: We randomly assigned 1415 patients referred for first pacemaker implantation to AAIR (n = 707) or DDDR (n = 708) pacing and followed them for a mean of 5.4 ± 2.6 years. The primary outcome was death from any cause. Secondary outcomes included paroxysmal and chronic atrial fibrillation, stroke, heart failure, and need for pacemaker reoperation. In the AAIR group, 209 patients (29.6%) died during follow-up vs. 193 patients (27.3%) in the DDDR group, hazard ratio (HR) 1.06, 95% confidence interval (CI) 0.88-1.29, P = 0.53. Paroxysmal atrial fibrillation was observed in 201 patients (28.4%) in the AAIR group vs. 163 patients (23.0%) in the DDDR group, HR 1.27, 95% CI 1.03-1.56, P = 0.024. A total of 240 patients underwent one or more pacemaker reoperations during follow-up, 156 (22.1%) in the AAIR group vs. 84 (11.9%) in the DDDR group (HR 1.99, 95% CI 1.53-2.59, P < 0.001). The incidence of chronic atrial fibrillation, stroke, and heart failure did not differ between treatment groups. CONCLUSION: In patients with sick sinus syndrome, there is no statistically significant difference in death from any cause between AAIR pacing and DDDR pacing. AAIR pacing is associated with a higher incidence of paroxysmal atrial fibrillation and a two-fold increased risk of pacemaker reoperation. These findings support the routine use of DDDR pacing in these patients. CLINICAL TRIAL REGISTRATION: URL http://www.clinicaltrials.gov. Unique identifier: NCT00236158.

Atrial fibrillation in recipients of cardiac resynchronization therapy device: 1-year results of the randomized MASCOT trial.

BACKGROUND: Atrial fibrillation (AF) is associated with increased morbidity and mortality in patients suffering from heart failure (HF). Patients in New York Heart Association HF classes III or IV, with systolic dysfunction and a wide QRS, are candidates for cardiac resynchronization therapy (CRT), and might benefit from atrial overdrive pacing (AOP). METHODS: The Management of Atrial fibrillation Suppression in AF-HF COmorbidity Therapy (MASCOT) trial enrolled 409 CRT device recipients (79% men), who were randomly assigned to AOP ON (n = 197), versus AOP OFF (n = 197) and followed up for 1 year. Their mean age was 68 +/- 10 years, left ventricular ejection fraction 25 +/- 6%, QRS duration 163 +/- 29 milliseconds. New York Heart Association class III was present in 86% of patients and 19% had a history of paroxysmal AF. The primary study end point was incidence of permanent AF at 1 year. RESULTS: Atrial overdrive pacing increased the percentage of atrial pacing from 30% to 80% (P < .0001), was well tolerated, and did not interfere with (a) delivery of CRT (95% mean ventricular pacing in both groups), (b) response to CRT (70% responders in the control vs 67% in the treatment group), or (c) cardiac function (left ventricular ejection fraction increased from 24.5% +/- 6.2% to 32.7% +/- 10.9% in the control and from 25.8% +/- 6.8% to 33.1% +/- 12.6% in the treatment group). The incidence of permanent AF was 3.3% in both groups. By logistic regression analysis, a history of AF (P < .001) and absence of antiarrhythmic drugs (P = .002) were associated with permanent AF. CONCLUSIONS: In this first trial of a specific AF prevention algorithm in CRT recipients, AOP was safe and did not worsen HF. The prevention algorithm did not lower the 1-year incidence of AF.

Sinus and paced P wave duration and dispersion as predictors of atrial fibrillation after pacemaker implantation in patients with isolated sick sinus syndrome.

The aim of this study was to prospectively evaluate the sinus and the paced P wave duration and dispersion as predictors of AF after pacemaker implantation in patients with isolated sick sinus syndrome (SSS). The study included 109 (69 women, mean age 72 +/- 11 years) patients with SSS, 59 with bradycardia-tachycardia syndrome (BTS). A 12-lead ECG was recorded before pacemaker implantation and during high right atrial and septal right atrial pacing at 70 and 100 beats/min. The ECGs were scanned into a computer and analyzed on screen. The patients were treated with AAIR (n = 52) or DDDR pacing. The P wave duration was measured in each lead and mean P wave duration and P wave dispersion were calculated for each ECG. AF during follow-up was defined as: AF in an ECG at or between follow-up visits; an atrial high rate episode with a rate of > or =220 beats/min for > or =5 minutes, atrial sensing with a rate of > or =170 beats/min in > or =5% of total counted beats, mode-switching in >/=5% of total time recorded, or a mode switching episode of > or =5 minutes recorded by the pacemaker telemetry. The ECG parameters were correlated to AF during follow-up. Mean follow-up was 1.5 +/- 0.9 years. None of the ECG parameters differed between patients with AF and patients without AF during follow-up, nor was there any difference between groups after correction for BTS and age. BTS was the strongest predictor of AF during follow-up (P < 0.001). P wave duration and dispersion measured before and during pacemaker implantation were not predictive of AF after pacemaker implantation in patients with isolated SSS.

Danish multicenter randomized study on fibrinolytic therapy versus acute coronary angioplasty in acute myocardial infarction: rationale and design of the DANish trial in Acute Myocardial Infarction-2 (DANAMI-2).

BACKGROUND: Randomized trials have indicated that primary coronary angioplasty performed in patients admitted directly to highly-experienced angioplasty centers offers certain advantages over intravenous fibrinolytic therapy. However, the large majority of patients with acute myocardial infarction are submitted to hospitals without a catheterization laboratory. This means that additional transportation will be necessary for many patients if a strategy of acute coronary angioplasty is to be introduced as routine treatment. The delay of treatment caused by transportation might negate (part of) the benefits of primary angioplasty compared to fibrinolytic therapy given immediately at the local hospital. STUDY DESIGN: The DANish trial in Acute Myocardial Infarction-2 (DANAMI-2) is the first large-scale study to clarify, in a whole community, which of the 2 treatment strategies is best. A total of 1900 patients with ST-elevation myocardial infarction are to be randomized: 800 patients will be admitted to invasive hospitals and 1100 patients will be admitted to referral hospitals. Half of the 1100 patients admitted to referral hospitals will immediately be transferred to an invasive center to be treated with primary angioplasty. IMPLICATIONS: If acute transfer from a local hospital to an angioplasty center is the superior strategy, primary angioplasty should be offered to all patients as routine treatment on a community basis.