Maze 3 for Atrial Fibrillation: Two Cuts Too Few?

The Maze procedure has been developed as a surgical approach to the management of patients with atrial fibrillation refractory to medical treatment. The recent modification of the technique (Maze 3) achieves good rate control with coordinated AV contractions. However, the procedure involves cuts that completely isolate a block of left atrial (LA) wall, including the four ostia of the pulmonary veins. The electrical and mechanical activity of this isolated LA block are dissociated from the rest of the atrium, and the area may, in fact, continue to fibrillate. This may provide a nidus for the development of mural thrombus. The weight and endocardial surface area of the LA block and of the entire LA were estimated in ten formalin fixed hearts from trauma victims with no evidence of cardiac disease. In these samples, the LA block represented 35% of the endocardial surface area of the entire LA and 29% of the weight. The LA block is of sufficient size to allow macroreentrant circuits to form and has the potential to fibrillate if isolated from the rest of the atrium. We modified the Maze 3 procedure to recruit the otherwise isolated LA block by using two additional cuts around each pair of pulmonary veins as they enter the LA. The first patient who underwent the modified procedure demonstrated sinus rhythm on Holter monitoring postoperatively and remained in sinus rhythm following burst atrial pacing at 300 and 420 beats/min each for 30 seconds. In addition, atrial contractions were found to contribute 19% of the cardiac output. The majority of the atrial wall and, in particular, the recruited area between the pulmonary veins contracted well, as demonstrated by transesophageal echocardiography. We suggest that this modification of Maze 3 has a potential advantage over the standard procedure by recruiting the entire LA without leaving any dyskinetic endocardial surface for thrombus formation. This should in turn reduce the risk of thromboembolic complications.     

Very Late Hazard with Stenting versus Balloon Angioplasty for ST‐Elevation Myocardial Infarction: A 16‐Year Single‐Center Experience

Objectives

This study compares very late outcomes following primary percutaneous coronary intervention for ST‐elevation myocardial infarction (STEMI) with stenting versus balloon angioplasty (BA).

Background

Stenting compared with BA for STEMI improves outcomes at 6–12 months, but comparisons beyond 6–12 months have not been studied. Recent studies have shown that stent thrombosis (ST) continues to increase beyond 3–5 years and may be higher with drug‐eluting stents (DES) than bare metal stents (BMS). We hypothesized that there may be a very late hazard with stenting versus BA due to very late ST.

Methods

From 1994 to 2010 consecutive patients with STEMI treated with BA (n = 601) or stenting (n = 1,594) were prospectively enrolled in our registry and followed for 1–16 years.

Results

Patients treated with BA were older, were more often female, had more three‐vessel disease, and had smaller vessels. Stented patients had trends for less stent/lesion thrombosis (ST/LT) and target vessel (TV) reinfarction at 1 year. In landmark analyses >1 year, stented patients had more very late ST/LT (6.1% vs. 2.9%, P = 0.002) and more TV reinfarction (7.9% vs. 3.1%, P < 0.001) which remained significant after adjusting for baseline risk. The greatest differences in very late outcomes were between DES and BA, but there were also significant differences between BMS and BA.

Conclusions

There appears to be a very late hazard with stenting versus BA for STEMI. These data should encourage new strategies for prevention of very late ST with both BMS and DES including the development of bio‐absorbable polymers and stent platforms. (J Interven Cardiol 2014;27:21–28)

     

DYSPLASTIC NEVI, CUTANEOUS MELANOMA, AND GYNECOLOGIC DISORDERS

We compared the frequency of reproductive system diseases and disorders among 206 female patients with dysplastic nevi (DN), and/or melanoma, in comparison with random samples of women of comparable age without melanoma. The highest odds ratio (OR) for these age-related diseases and reproductive disorders occurs among the youngest age group of the patients with DN alone (mean age 35.1 +/- 1.2 yr): 44.2% of the DN subjects had one or more reproductive disorders compared with 19.8% of the random sample (OR 3.2, 95% CL (1.6, 6.5), P less than 0.001). The patients with melanoma and DN (mean age 41.5 +/- 1.4 yr) also had a significantly greater percentage of subjects with one or more reproductive disorders, though less so than the DN subjects: 49.4% compared to 33.7% (OR 1.9, 95% CL (1.1, 3.3), P = 0.02).     

Use of heparins in Non-ST-elevation acute coronary syndromes

Purpose

We describe the use of antithrombotic therapy in the management of patients with acute coronary syndromes.

Methods

Patients from the Global Registry of Acute Coronary Events, a multinational coronary disease registry, were characterized according to the early and continued use of low-molecular-weight heparin, unfractionated heparin, any crossover of heparin therapy (change in early vs late heparin treatment), and no heparin treatment. Hospital outcomes were analyzed according to the heparin treatment and the timing of percutaneous coronary interventions.

Results

Data from 23,172 patients with non-ST-segment elevation myocardial infarction or unstable angina were analyzed. A total of 8791 patients were treated with low-molecular-weight heparin within the first 24 hours and continued thereafter; 4076 patients received unfractionated heparin; 2953 patients received neither heparin therapy; and 7352 patients received crossover heparin treatment. Concomitant treatment, including early or late percutaneous coronary intervention, varied according to the type of heparin therapy. Patients treated with a crossover therapy were more likely to undergo percutaneous coronary intervention. The rates of major bleeding and death were lower with low-molecular-weight heparin (1.4% and 1.8%, respectively) compared with unfractionated heparin (1.9% and 2.5%, respectively), crossover heparin (2.0% and 2.3%, respectively), or neither heparin (1.5% and 2.4%, respectively).

Conclusions

There is significant variability in heparin use in patients with acute coronary syndromes. Heparin type and use seem to be related to the timing and use of percutaneous coronary interventions. The early use of low-molecular-weight heparin in the setting of an acute coronary syndrome is associated with better short-term outcomes.     

External validity of clinical trials in acute myocardial infarction

BACKGROUND: Patients enrolled in randomized clinical trials (RCTs) may not reflect those seen in real-life practice. Our goal was to compare patients eligible for enrollment but not enrolled in contemporary RCTs of reperfusion therapy with patients who would have been ineligible and also with patients with acute myocardial infarction (AMI) participating in RCTs. METHODS: Consecutive patients with AMI (n = 8469) enrolled in the GRACE registry (Global Registry of Acute Coronary Events) were divided into 3 groups: RCT participants (11%; n = 953), eligible nonenrolled patients (55%; n = 4669), and ineligible patients (34%; n = 2847). Our main outcome measures were hospital mortality rates. RESULTS: Based on baseline characteristics or GRACE risk-score distribution, RCT participants had the lowest a priori risk of death; eligible patients had a higher risk; and ineligible patients had the highest risk. Actual hospital mortality showed a similar gradient (3.6%, 7.1%, and 11.4%, respectively) (P<.001). Multivariable analysis adjusting for baseline risk, use and type of reperfusion therapy, and delay from symptom onset to admission consistently showed a higher mortality rate for eligible nonenrolled patients than for RCT participants (odds ratio, 1.61; 95% confidence interval, 1.06-2.43; and odds ratio, 1.97; 95% confidence interval, 1.24-3.13, respectively). CONCLUSIONS: Patients with AMI participating in RCTs have a lower baseline risk and experience lower mortality than nonenrolled patients, even when they are trial eligible. This difference is not entirely explained by differences in baseline risk, use and type of reperfusion therapy, and/or delays in presentation. Caution is necessary when extending the findings obtained in RCTs to the general population with AMI.     

Impact of prior peripheral arterial disease and stroke on outcomes of acute coronary syndromes and effect of evidence-based therapies (from the Global Registry of Acute Coronary Events)

We assessed the effect of previous peripheral arterial disease (PAD) and stroke on clinical outcomes in patients with acute coronary syndrome (ACS) and sought to ascertain the effectiveness of evidence-based therapies in these patients. We used data from the multinational Global Registry of Acute Coronary Events. Patients were enrolled at 102 hospitals in 13 countries between April 1999 and September 2005. Patients presenting with ACS were stratified according to the presence of previous PAD, stroke, PAD and stroke, or neither. In-hospital analysis included 48,418 patients and 6-month analysis included 32,735 patients. The primary end point was all-cause mortality and major adverse cardiac events during 6-month follow-up. Adverse in-hospital and 6-month events were lowest in patients with neither PAD nor stroke and highest in patients with PAD and stroke after adjustment for baseline demographics and co-morbidities. In-hospital mortality for the 4 groups (neither, PAD, stroke, PAD and stroke) was 4.5% versus 7.2% versus 8.9% versus 9.4% (p <0.001) and that for 6-month mortality was 3.9% versus 8.8% versus 9.3% versus 12%, and these differences persisted after accounting for differences in baseline characteristics. Use of evidence-based therapies was associated with significantly less morbidity and mortality in all ACS subgroups. In conclusion, outcomes after ACS are worse in patients with PAD or stroke, with the highest risk in patients with the 2 conditions and the use of evidence-based therapies are associated with improved outcomes in all ACS subgroups.