Intraaortic Balloon Pump vs Peripheral Ventricular Assist Device Use in the United States.

BACKGROUND: The objective of this study was to characterize practical use trends and outcomes for intraaortic balloon pump (IABP) and percutaneous left ventricular assist device (pVAD) use in cardiogenic shock at a national level. METHODS: An analysis of all adult patients admitted nonelectively for cardiogenic shock from January 2008 through December 2017 was performed using the National Inpatient Sample. Trends of inpatient IABP and pVAD use were analyzed using survey-weighted estimates and the modified Cochran-Armitage test for significance. Multivariable regression models and inverse probability of treatment weights were used to perform risk-adjusted analyses of pVAD mortality, a composite of adverse events (AE), and resource use, with IABP as reference. RESULTS: Of an estimated 774,310 patients admitted with cardiogenic shock, 143,051 received a device: IABP, 127,792 (16.5%); or pVAD, 15,259 (2.0%). IABP use decreased (23.8% to 12.7%; P for trend <.001), whereas pVAD implantation increased significantly during the study period (0.2% to 4.5%; P for trend <.001). Inverse probability of treatment weights demonstrated significantly higher odds of mortality with pVAD (odds ratio, 1.9; 95% confidence interval, 1.7 to 2.2), but not AE (odds ratio, 1.1; 95% confidence interval, 0.96 to 1.27), compared with IABP. After risk adjustment, pVAD use was associated with an additional $15,202 (P < .001) in cost for survivors and $29,643 for nonsurvivors (P < .001). CONCLUSIONS: Over the study period, the rate of pVAD use for cardiogenic shock significantly increased. Compared with IABP, pVAD use was associated with increased mortality, higher costs, and several AEs. Multi-institutional clinical trials with rigorous inclusion criteria are warranted to evaluate the clinical utility of pVADs in the modern era.

Vegetarian diets and cardiovascular risk factors in black members of the Adventist Health Study-2.

OBJECTIVE: To compare cardiovascular risk factors between vegetarians and non-vegetarians in black individuals living in the USA. DESIGN: A cross-sectional analysis of a sub-set of 592 black women and men enrolled in the Adventist Health Study-2 (AHS-2) cohort of Seventh-day Adventists. SETTING: Members of the AHS-2 cohort, who lived in all states of the USA and provinces of Canada. SUBJECTS: Black/African-American members of two sub-studies of AHS-2 where blood and physiological measurements were obtained. RESULTS: Of these women and men, 25% were either vegan or lacto-ovo-vegetarians (labelled 'vegetarian/vegans'), 13% were pesco-vegetarian and 62% were non-vegetarian. Compared with non-vegetarians, the vegetarian/vegans had odds ratios for hypertension, diabetes, high blood total cholesterol and high blood LDL-cholesterol of 0·56 (95% CI 0·36, 0·87), 0·48 (95% CI 0·24, 0·98), 0·42 (95% CI 0·27, 0·65) and 0·54 (95% CI 0·33, 0·89), respectively, when adjusted for age, gender, education, physical activity and sub-study. Corresponding odds ratios for obesity in vegetarian/vegans and pesco-vegetarians, compared with non-vegetarians, were 0·43 (95% CI 0·28, 0·67) and 0·47 (95% CI 0·27, 0·81), respectively; and for abdominal obesity 0·54 (95% CI 0·36, 0·82) and 0·50 (95% CI 0·29, 0·84), respectively. Results for pesco-vegetarians did not differ significantly from those of non-vegetarians for other variables. Further adjustment for BMI suggested that BMI acts as an intermediary variable between diet and both hypertension and diabetes. CONCLUSIONS: As with non-blacks, these results suggest that there are sizeable advantages to a vegetarian diet in black individuals also, although a cross-sectional analysis cannot conclusively establish cause.

Vegetarian diets and blood pressure among white subjects: results from the Adventist Health Study-2 (AHS-2).

OBJECTIVE: Previous work studying vegetarians has often found that they have lower blood pressure (BP). Reasons may include their lower BMI and higher intake levels of fruit and vegetables. Here we seek to extend this evidence in a geographically diverse population containing vegans, lacto-ovo vegetarians and omnivores. DESIGN: Data are analysed from a calibration sub-study of the Adventist Health Study-2 (AHS-2) cohort who attended clinics and provided validated FFQ. Criteria were established for vegan, lacto-ovo vegetarian, partial vegetarian and omnivorous dietary patterns. SETTING: Clinics were conducted at churches across the USA and Canada. Dietary data were gathered by mailed questionnaire. SUBJECTS: Five hundred white subjects representing the AHS-2 cohort. RESULTS: Covariate-adjusted regression analyses demonstrated that the vegan vegetarians had lower systolic and diastolic BP (mmHg) than omnivorous Adventists (ß = -6.8, P < 0.05 and ß = -6.9, P < 0.001). Findings for lacto-ovo vegetarians (ß = -9.1, P < 0.001 and ß = -5.8, P < 0.001) were similar. The vegetarians (mainly the vegans) were also less likely to be using antihypertensive medications. Defining hypertension as systolic BP > 139 mmHg or diastolic BP > 89 mmHg or use of antihypertensive medications, the odds ratio of hypertension compared with omnivores was 0.37 (95 % CI 0.19, 0.74), 0.57 (95 % CI 0.36, 0.92) and 0.92 (95 % CI 0.50, 1.70), respectively, for vegans, lacto-ovo vegetarians and partial vegetarians. Effects were reduced after adjustment for BMI. CONCLUSIONS: We conclude from this relatively large study that vegetarians, especially vegans, with otherwise diverse characteristics but stable diets, do have lower systolic and diastolic BP and less hypertension than omnivores. This is only partly due to their lower body mass.

Recovery of mitral isthmus conduction leads to the development of macro-reentrant tachycardia after left atrial linear ablation for atrial fibrillation.

BACKGROUND: Left atrial linear ablation for atrial fibrillation (AF) may be proarrhythmic, leading to left atrial macro-reentrant tachycardia (LAT). Whether due to failure to achieve block initially or to recovery of conduction after ablation is unknown. This study was designed to evaluate the frequency of recovery of mitral isthmus (MI) conduction compared with cavo-tricuspid isthmus (CTI) conduction, and the relationship between recovery of MI conduction and postablation LAT. METHODS AND RESULTS: Of 163 patients with AF who underwent circumferential pulmonary vein ablation plus left atrial linear ablation, in whom MI and CTI ablation produced bidirectional conduction block, 52 underwent repeat ablation for recurrent atrial arrhythmias (AF or LAT). Of these 52 patients, coronary sinus ablation was required in 48 to achieve bidirectional MI block at the index ablation. During repeat ablation, MI and CTI conduction was assessed in sinus rhythm. At repeat ablation, MI conduction had recovered in 38 of 52 patients, as compared with CTI conduction which recovered in only 12 of 52 patients (P=0.001). At repeat ablation, the recurrent clinical arrhythmia in 12 patients was MI-dependent LAT. Recovery of MI conduction was associated with development of MI-dependent LAT (P=0.01). CONCLUSIONS: Despite using bidirectional conduction block as a procedural end point, recovery of MI conduction is common and may lead to LAT after left atrial linear ablation for AF. The reason for greater recovery of MI versus CTI conduction is unknown but could be due to differences in isthmus anatomy or lower power used for ablation in the left versus right atrium.

A rare case of amiodarone-induced hypothyroidism presenting with cardiac tamponade.

Subclinical pericardial effusions are common in patients with untreated hypothyroidism and usually resolve with thyroid replacement therapy, but cardiac tamponade is a rare presentation of prolonged untreated hypothyroidism. We report the first case of cardiac tamponade due to hypothyroidism produced by administration of amiodarone.

Circumferential pulmonary vein ablation with additional linear ablation results in an increased incidence of left atrial flutter compared with segmental pulmonary vein isolation as an initial approach to ablation of paroxysmal atrial fibrillation.

BACKGROUND: There has been growing concern that linear ablation is associated with an increased risk of iatrogenic arrhythmias in patients undergoing ablation for atrial fibrillation (AF). Therefore, we compared circumferential pulmonary vein ablation plus left atrial linear ablation (CPVA+LALA) with segmental pulmonary vein isolation (PVI)in patients with paroxysmal AF. METHODS AND RESULTS: Sixty-six consecutive patients with paroxysmal AF were prospectively randomly assigned to receive PVI versus CPVA+LALA (consisting of encircling lesions around the pulmonary veins), a roof line, and a mitral isthmus line with documentation of bidirectional mitral isthmus block. All patients were seen at 1, 3, 6, and every 12 months after ablation, with 14-day continuous ECG monitoring every 6 months. At 16.4+/-6.3 months after 1 ablation procedure, 19 patients (58%) remained free of atrial arrhythmias after PVI versus 17 patients (51%) after CPVA+LALA (P=0.62). After PVI, 14 patients had recurrent paroxysmal AF, whereas after CPVA+LALA, 8 patients had recurrent AF, 6 had atypical left atrial flutter (LAFL), and 2 had both AF and LAFL (P=0.32 between PVI versus CPVA+LALA for AF but P=0.002 for LAFL). Twenty-eight patients (85%) remained arrhythmia-free after 1.3+/-0.5 PVI procedures versus 28 patients (85%) after 1.4+/-0.6 CPVA+LALA procedures (P=NS). Fluoroscopy time was longer after CPVA+LALA versus PVI (91 versus 73 minutes, P=0.04). CONCLUSIONS: As an initial ablation approach in patients with paroxysmal AF, more LAFL occurred after CPVA+LALA and fluoroscopy times were longer compared with segmental PVI.

Effect of mitral isthmus block on development of atrial tachycardia following ablation for atrial fibrillation.

BACKGROUND: Successful mitral isthmus (MI) ablation may reduce recurrence of atrial fibrillation (AF) and macro-reentrant atrial tachycardia (AT) after pulmonary vein isolation (PVI) for AF. OBJECTIVE: To determine if achieving bidirectional MI conduction block (MIB) during circumferential pulmonary vein ablation (CPVA) plus left atrial linear ablation (LALA) affects development of AT. METHODS: Sixty consecutive patients with persistent (n = 25) or paroxysmal (n = 35) AF undergoing CPVA plus LALA at the MI and LA roof were evaluated in a prospective, nonrandomized study. RESULTS: PVI was achieved in all patients. Bidirectional MI block was achieved in 50 of 60 patients (83%). During 18 +/- 5 months follow-up, 12 patients (20%) developed recurrent AF and 15 (25%) developed AT. Patients in whom MIB was not achieved at initial ablation had four times higher risk of developing AT (P = 0.008, 95% confidence interval 1.43-11.48) versus patients with MIB. In 12 patients with AT undergoing repeat ablation, 22 ATs were identified, with reentry involving the MI in nine, the LA roof in six, and the ridge between the LA appendage and left PVs in seven. In patients with MIB at initial ablation, recovery of MI conduction was seen in eight of 13 undergoing repeat ablation. CONCLUSIONS: AT occurring after CPVA plus LALA is often due to incomplete MI ablation, but may also occur at the LA roof, and ridge between the LA appendage and left PVs. Failure to achieve MI block increases the risk of developing AT. Resumption of MI conduction may also be a mechanism for AT recurrence. (PACE 2010; 460-468).

Five-year outcomes after segmental pulmonary vein isolation for paroxysmal atrial fibrillation.

Most studies evaluating the efficacy of atrial fibrillation (AF) ablation report follow-up periods of 1 year to 2 years, but few report long-term results of > or =5 years after ablation. Therefore, we evaluated the long-term efficacy (i.e., >5 years) of segmental antrum pulmonary vein isolation (PVI) for paroxysmal AF. Seventy-one patients (60 +/- 10 years, 56 men) who underwent PVI for paroxysmal AF from January 1, 2002, to August 31, 2003, were followed for at least 5 years after their index ablation procedure. Five-year outcomes were determined at last clinic visit, by telephone encounters, and by cardiac monitoring when available. After 1 ablation, off antiarrhythmic drugs, 61 patients (86%) were free of symptomatic AF at 12 months, 56 patients (79%) at 24 months, and 40 patients (56%) at 63 +/- 5 months. Sixteen patients (22.5%) had AF recur after the second year after ablation. Thirty-one patients underwent > or =1 repeat ablations (1.6 +/- 0.9 per patient). After multiple procedures, 58 patients (81%) were free of symptomatic AF off antiarrhythmic drugs at 63 +/- 5 months after their initial ablation; however, in 18 of these patients who received multiple ablation procedures, mean duration of follow-up after the last ablation was only 13.5 +/- 2.1 months. In conclusion, overall 5-year outcome after PVI for paroxysmal AF is similar to that previously reported for shorter-term follow-up (< or =2 years). However, late recurrences >2 years after initial ablation were frequent, and repeat ablation was often required to maintain freedom from symptomatic AF.

Diagnosis and management of typical atrial flutter.

Typical atrial flutter (AFL) is a common atrial arrhythmia that may cause significant symptoms and serious adverse effects including embolic stroke, myocardial ischemia and infarction, and rarely a tachycardia-induced cardiomyopathy as a result of rapid atrioventricular conduction. As a result of the well-defined anatomic and electrophysiological substrate, and the relative pharmacologic resistance of typical AFL, radiofrequency catheter ablation has emerged in the past decade as a safe and effective first-line treatment. This article reviews the electrophysiology of typical AFL and the techniques currently used for its diagnosis and management.