Israel Medical Association Journal

Background: Atrial fibrillation (AF) is a common complication of coronary artery bypass graft (CABG) surgery, occurring in 20%–40% of patients, mostly during the first week after surgery. It is associated with increased morbidity and mortality, but data are limited. 

Objectives: To assess the correlation between new-onset in-hospital AF following CABG and long-term AF, cerebrovascular accident (CVA), or death.

Methods: We conducted an analysis of 161 consecutive patients who underwent isolated CABG surgery in a tertiary center during the period 2002–2003. 

Results: Patients’ mean age was 72 years, and the majority were males (77%). Approximately half of the patients experienced prior myocardial infarction, and 14% had left ventricular ejection fraction < 40%. Postoperative AF (POAF) occurred in 27% of the patients. Patients were older and had larger left atrium diameter. POAF was strongly correlated with late AF (OR 4.34, 95%CI 1.44–13.1, P = 0.01) during a mean follow-up of 8.5 years. It was also correlated with long-term stroke but was not associated with long-term mortality. 

Conclusions: POAF is a common complication of CABG surgery, which is correlated with late AF and stroke. Patients with POAF should be closely monitored to facilitate early administration of anticoagulant therapy in a high risk population upon recurrence of AF. 

 

Background: Syncope is a common clinical condition spanning from benign to life-threatening diseases. There is sparse information on the outcomes of syncopal patients who received an implantable cardiac defibrillator (ICD) for primary prevention of sudden cardiac death (SCD). 

Objectives: To assess the outcomes and prognosis of patients who underwent implantable cardiac defibrillator (ICD) implantation for primary prevention of SCD and compare them to patients who presented with or without prior syncope.

Methods: We compared the medical records of 75 patients who underwent ICD implantation for primary prevention of SCD and history of syncope to those of a similar group of 80 patients without prior syncope. We assessed the episodes of ventricular tachycardia (VT), ventricular fibrillation (VF), shock, anti-tachycardia pacing (ATP) and mortality in each group during follow-up.

Results: Mean follow-up was 893 days (810–976, 95%CI) (no difference between groups). There was no significant difference in gender or age. Patients with prior syncope had a higher ejection fraction rate (35.5 ± 12.6 vs. 31.4 ± 8.76, P = 0.02), experienced more episodes of VT (21.3% vs. 3.8%, P = 0.001) and VF (8% vs. 0%, P = 0.01), and received more electric shocks (18.7% vs. 3.8%, P = 0.004) and ATP (17.3% vs. 6.2%, P = 0.031). There were no differences in inappropriate shocks (6.7% vs. 5%, P = 0.74), cardiovascular mortality (cumulative 5 year estimate 29.9% vs. 32.2%, P = 0.97) and any death (cumulative 5 year estimate 38.1% vs. 48.9%, P = 0.18).

Conclusions: Patients presenting with syncope before ICD implantation seemed to have more episodes of VT/VF and shock or ATP. No differences in mortality were observed

 

Background: The kinetics of high sensitivity cardiac troponin T (hs-cTnT) levels after elective, biphasic, direct-current cardioversion for persistent atrial fibrillation/flutter remains unknown.

Methods: We examined hs-cTnT kinetics in 24 patients at baseline and at 2, 6 and 24 hours post-cardioversion, and again at 7 and 30 days. We also examined levels of creatine kinase, aspartate aminotransferase, lactate dehydrogenase, brain natriuretic peptide (BNP), and high sensitivity C-reactive protein (hs-CRP).

Results: Median (25th, 75th interquartiles) baseline hs-cTnT concentration was 19.8 (10.4, 35.2) ng/L with 14 patients presenting with levels above the 99th percentile (13 ng/L). Hs-cTnT levels did not change significantly over time although they tended to decrease by 30 days, 18.8 ng/L (12.5, 23.3). There was no significant rise in other markers of myocardial injury. Similarly, BNP and hs-CRP levels were elevated at baseline and tended to decrease over time.

Conclusions: Patients with persistent atrial fibrillation/flutter have elevated hs-cTnT levels, as part of a general rise in biomarkers such as BNP and hs-CRP, without a further rise after cardioversion. After cardioversion, there is a gradual non-significant decrease in biomarker levels over time, and thus a rise in hs-cTnT levels should not be attributed to cardioversion. 

 

Background: Stroke is a leading cause of death and disability worldwide. The risk factors for stroke overlap those for cardiovascular disease. Atrial fibrillation (AF) is a particularly strong risk factor and is common, particularly in the elderly. Maccabi Healthcare Services (MHS) has maintained a vascular registry of clinical information for over 100,000 members, among them patients with heart disease and stroke. 

Objectives: To determine the prevalence of stroke in MHS, and whether the association of AF and stroke, along with other risk factors, in the Maccabi population is similar to that in published studies.

Methods: Data on stroke and AF patients aged 45 and older were collected from the database for the year 2010, including age, previous transient ischemic attack (TIA), body mass index (BMI), prior myocardial infarction (MI), diabetes, hypertension, anticoagulation and dyslipidemia. A cross-sectional analysis was used to estimate stroke prevalence by AF status. A case-control analysis was also performed comparing a sample of stroke and non-stroke patients. This permitted estimation of the strength of associations for atrial fibrillation and various other combinations of risk factors with stroke. 

Results: Stroke prevalence ranged from 3.5 (females, age 45–54 years) to 74.1 (males, age 85+) per thousand in non-AF members, and from 29 (males, age 45–54) to 165 (males, age 85+) per thousand for patients with AF. AF patients had significantly more strokes than non-AF patients in all age groups. Stroke prevalence increased with age and was significantly higher in males. Multivariable analysis revealed that male gender, increasing age, AF, hypertension, diabetes, and history of TIA were highly significant risk factors for stroke. In addition, for males, dyslipidemia and prior MI were moderately strong risk factors. 

Conclusions: Analysis of the MHS vascular database yielded useful information on stroke prevalence and association of known risk factors with stroke, which is consistent with the epidemiological literature elsewhere. Further analysis of health fund data could potentially provide useful information in the future. 

 

Background: Hypertrophic cardiomyopathy (HCM) is a familial disease with autosomal dominant inheritance and age-dependent penetrance, caused primarily by mutations of sarcomere genes. Because the clinical variability of HCM is related to its genetic heterogeneity, genetic studies may improve the diagnosis and prognostic evaluation in HCM.

Objectives: To analyze the impact of genetic diagnosis on the clinical management of HCM.

Methods: Genetic studies were performed for either research or clinical reasons. Once the disease-causing mutation was identified, the management plan was reevaluated. Family members were invited to receive genetic counseling and encouraged to be tested for the mutation.

Results: Ten mutations in sarcomere protein genes were identified in 9 probands: 2 novel and 8 previously described. Advanced heart failure or sudden death in a young person prompted the genetic study in 8 of the 9 families. Of 98 relatives available for genotyping, only 53 (54%) agreed to be tested. The compliance was higher in families with sudden death and lower in what appeared to be sporadic HCM or elderly-onset disease. Among the healthy we identified 9 carriers and 19 non-carriers. In 6 individuals the test result resolved an uncertainty about "possible HCM." In several cases the genetic result was also used for family planning and played a role in decisions on cardioverter-defibrillator implantation.

Conclusions: Recurrence of a same mutation in different families created an opportunity to apply the information from the literature for risk stratification of individual patients. We suggest that the clinical context determine the indication for genetic testing and interpretation of the results.