Relationship between obstructive coronary artery disease and abnormal stress testing in patients with paroxysmal or persistent atrial fibrillation

Comparative characteristics of a pacemaker implantation after biatrial or left atrial ablation of atrial fibrillation in combination with coronary artery bypass grafting in patients with ischemic heart disease and long-standing persistent atrial fibrillation

Aim      To compare the incidence of a permanent pacemaker (PP) implantation based on the chosen treatment technology (biatrial ablation, BA, or left atrial ablation (LAA) for long-standing persistent atrial fibrillation (AF) with simultaneous coronary bypass (CB).Material and methods  The study included 116 patients with long-standing persistent AF and indications for CB. Patients were randomized to two equal groups (58 patients in each). Group 1 underwent BA in combination with CB; group 2 patients underwent isolated LAA with simultaneous CB under the conditions of artificial circulation. Incidence of PP implantation was assessed during the early (to 30 days) and late (to 60 months) postoperative periods.Results For the observation period, a total of 9 PPs was implanted in both groups, 6 in the BA group and 3 in the LAA group (odds ratio, OR, 0.5; 95 % confidence interval, CI, 0.1-2.4; р=0.490). During the early postoperative period, 5 patients in the BA group and 2 patients in the LAA group were implanted with PP (OR, 0.4; 95 % CI. 0-2.5; р=0.438). During the late postoperative period, one (2%) patient of the BA group was implanted with a permanent PP at 30 months of follow-up due to the development of sick sinus syndrome (SSS); also, one (2%) patient of the LAA group required PP implantation at 54 months of follow-up due to the development of SSS. The causes for PP implantation in the BA group included the development of complete atrioventricular (AV) block in 9 % of cases (95 % CI, 4-19 %); sinus node dysfunction and junctional rhythm in 2 % of cases (95 % CI, 0-9 %). Compared to this group, the LAA group showed a statistically significant difference in the incidence of AV block (0 cases, р=0.047). The major cause for PP implantation in the LAA group was the development of sinus node dysfunction in 3 (5 %) patients (95 % CI, 2-14 %).Conclusion      The use of BA in surgical treatment of long-standing persistent AF with simultaneous myocardial revascularization is associated with a high risk of AV block, which requires permanent PP implantation in the postoperative period. Total incidence of permanent PP implantation for dysfunction of the cardiac conduction system following the combination surgical treatment of long-standing persistent AF and IHD, either CB and LAA or BA, did not differ between the treatment groups both in early and late postoperative periods.

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress tests

OBJECTIVES

Many patients with atrial fibrillation (AF) or atrial flutter (AFL) and rapid ventricular response (RVR) have elevated high-sensitivity troponin T (hsTnT) values. Elevated hsTnT is an independent risk marker for cardiovascular events and mortality. The aim was to examine if AF/AFL patients with RVR and elevated hsTnT have an increased incidence of pathological cardiac stress tests, indicating need of further evaluation for coronary artery disease (CAD). Design: We prospectively included 90 AF/AFL patients without known heart failure and CAD presenting with AF/AFL and RVR. Half of the patients had elevated hsTnT (cases) and half had levels below the 99th percentile (controls). All patients were discharged in sinus rhythm. After approximately one week in sinus rhythm a new hsTnT was analysed and the patients performed a bicycle exercise stress test within the 30 day follow-up. The primary endpoint was a pathological stress test confirmed by a pathological SPECT myocardial perfusion imaging or a coronary angiography. Results: None of the controls reached the primary endpoint. Two patients (4%) out of the 45 cases reached the primary endpoint (p = .49 vs controls), but only one was found to have significant CAD at subsequent coronary angiography. Conclusion: Patients with paroxysmal AF/AFL, without a history of CAD and heart failure, who present with a RVR and minor hsTnT elevations were not found to have an increased incidence of pathological stress tests compared to patients with hsTnT values below the 99th percentile.

Diagnostic role of coronary CT angiography in paroxysmal or first diagnosed atrial fibrillation

OBJECTIVES

The presence of coronary artery disease (CAD) in patients hospitalised with paroxysmal or first diagnosed atrial fibrillation (AF) has major implications for antithrombotic therapy and cardiovascular event rate. Coronary CT angiography (CCTA) is a feasible tool to identify patients with concealed CAD. We aimed to evaluate the diagnostic role of early CCTA in patients hospitalised with paroxysmal or first diagnosed AF.

METHODS

In a 5-year single-centre retrospective analysis, 566 patients with paroxysmal or first diagnosed AF who underwent CCTA were enrolled to investigate the presence of CAD.

RESULTS

In patients with paroxysmal or first diagnosed AF, CCTA revealed CAD (coronary artery stenosis ≥50%) in 39.2%. Cardiac catheterisation was performed in 31.6%, confirming CAD in 13.1% of all patients. In 8.0% percutaneous coronary intervention and in 0.5% coronary artery bypass grafting was performed. In patients with paroxysmal or first diagnosed AF: (1) angina pectoris per se does not predict CAD; (2) multivariable regression analysis revealed age, male sex and diabetes as risk factors for CAD in AF; (3) Framingham Risk Score for coronary heart disease and CHA2DS2-VASc-Score were relevant risk scores of CAD and (4) the classification of Coronary Artery Calcium score reference values according to the Multi-Ethnic Study of Atherosclerosis was a predictor of CAD.

CONCLUSION

Patients with paroxysmal or first diagnosed AF are at risk for CAD, while CCTA is a feasible diagnostic tool for CAD. We recommend to integrate CT calcium scoring and CCTA into the diagnostic workup of patients with new-onset or paroxysmal AF.

Cardiovascular Calcification as a Marker of Increased Cardiovascular Risk and a Surrogate for Subclinical Atherosclerosis: Role of Echocardiography

The risk prediction of future cardiovascular events is mainly based on conventional risk factor assessment by validated algorithms, such as the Framingham Risk Score, the Pooled Cohort Equations and the European SCORE Risk Charts. The identification of subclinical atherosclerosis has emerged as a promising tool to refine the individual cardiovascular risk identified by these models, to prognostic stratify asymptomatic individuals and to implement preventive strategies. Several imaging modalities have been proposed for the identification of subclinical organ damage, the main ones being coronary artery calcification scanning by cardiac computed tomography and the two-dimensional ultrasound evaluation of carotid arteries. In this context, echocardiography offers an assessment of cardiac calcifications at different sites, such as the mitral apparatus (including annulus, leaflets and papillary muscles), aortic valve and ascending aorta, findings that are associated with the clinical manifestation of atherosclerotic disease and are predictive of future cardiovascular events. The aim of this paper is to summarize the available evidence on clinical implications of cardiac calcification, review studies that propose semiquantitative ultrasound assessments of cardiac calcifications and evaluate the potential of ultrasound calcium scores for risk stratification and prevention of clinical events.

[Association of Atrial Fibrillation with Coronary Lesion in Ischemic Heart Disease Patients]

AIM

to find out whether atrial fibrillation (AF) in patients with ischemic heart disease (IHD) is related to some definite localization or extent of coronary artery lesions or type of coronary circulation.

MATERIALS AND METHODS

We compared data of clinical, laboratory, and instrumental examination of 178 IHD patients from the Registry of coronary angiography of patients with AF (main group) and 331 patients (comparison group) selected according to propensity score matching with balancing by sex, age, body mass index, severity of chronic heart failure, frequency of myocardial infarctions, detection of arterial hypertension, and thyroid diseases.

RESULTS

The groups did not differ in terms of alcohol use, frequency of smoking, and detection of diabetes. Patients with AF compared with those without had higher mean heart rate (105±32 vs. 70±13 bpm, р<0.001), lower level of triglycerides (1.74±1.08 vs. 1.94±1.17 mmol / l, р=0.019). AF patients more rarely had class III-IV effort angina (52.9 % vs. 66.5 %, р=0.041). Rate of detection of left ventricular (LV) dilatation and index of LV asynergy in both groups were similar, but absolute dimensions and indexes of LV, left atrium, right ventricle, LV myocardial mass were higher in the AF group. Hemodynamically significant mitral regurgitation and lowering of LV contractility were more often detected in patients with AF (49.1 % vs. 18.4 %, р<0.001, and 56.2 % vs. 39.5 %, р<0.001, in main and comparison groups, respectively). Analysis of coronary angiography data showed that patients with compared with those without AF more often had right type of coronary circulation (87.5 % vs. 80.4 %, р=0.043) as well as lesions of the right coronary artery (92.1 % vs. 85.8 %, р=0.037), and less often lesions of left coronary artery trunk (16.3 % vs. 24.8 %, р=0.027).

CONCLUSION

AF in patients with IHD is associated with right coronary artery lesions and right type of coronary circulation.

Dynamic high-sensitivity troponin elevations in atrial fibrillation patients might not be associated with significant coronary artery disease

Background

Since the introduction of high-sensitivity troponin assays a greater proportion of atrial fibrillation (AF) patients present with dynamic troponin elevations. We hypothesize that significant coronary artery disease (CAD) causes relative ischemia in the setting of a rapid heart rate resulting in dynamic troponin elevation. The aim of this study was to examine if patients without known CAD who present with AF, tachycardia and dynamic high-sensitivity troponin T (hsTnT) change have an increased risk of cardiac events.

Methods

We retrospectively included AF patients presenting with tachycardia during one year. The primary endpoint was acute coronary syndrome, revascularization or death due to ischemic heart disease during 30 months follow-up.

Results

Five hundred twenty-two patients without known CAD were included, 300 (57%) had normal hsTnT and 49 (9.5%) had dynamic hsTnT elevation. During follow-up 12 (4%) patients with normal hsTnT reached the primary endpoint and a total of 14 (4.7%) patients died. In the group with dynamic hsTnT the results were 4 (8.2%) and 12 (25%) respectively. The age-adjusted hazard ratio (HR) for the primary endpoint in patients with dynamic hsTnT was 1.9 (95% CI: 0.6 to 6.2; p = 0.28) and for all-cause mortality 3.8 (95% CI: 1.7 to 8.5; p = 0.001).

Conclusions

Dynamic hsTnT elevation in connection with AF might not be associated with any major increased risk of coronary events, but indicates increased all-cause mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-017-0601-7) contains supplementary material, which is available to authorized users.

Risk of Atrial Fibrillation or Flutter Associated with Periodontitis: A Nationwide, Population-Based, Cohort Study

OBJECTIVE

To investigate the risk of atrial fibrillation or atrial flutter in patients with periodontitis (PD) in comparison with individuals without PD.

METHODS

We used the 1999-2010 Taiwanese National Health Insurance Research Database to identify cases of PD in the year 2000 matching (1:1) with persons without PD during 1999-2000 according to sex and individual age as the control group. Using Cox proportional regression analysis adjusting for potential confounders, including age, sex, and comorbidities at baseline, and average annual number of ambulatory visits and dental scaling frequency during the follow-up period, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) to examine the risk of atrial fibrillation or flutter in PD patients in comparison with the control group. Subgroup analyses according to age, gender, or comorbidities were conducted to study the robustness of the association and investigate possible interaction effects.

RESULTS

We enrolled 393,745 patients with PD and 393,745 non-PD individuals. The incidence rates of atrial fibrillation or flutter were 200 per 105 years among the PD group and 181 per 105 years in the non-PD group (incidence rate ratio, 1.10; 95% CI, 1.06-1.14). After adjusting for potential confounders, we found an increased risk of atrial fibrillation or flutter in the PD group compared with the non-PD group (HR, 1.31; 95% CI, 1.25-1.36). The greater risk of atrial fibrillation or flutter in the PD group remained significant across all disease subgroups except hyperthyroidism and sleep apnea.

CONCLUSION

The present study results indicate an increased risk of atrial fibrillation or flutter in patients with PD. Lack of individual information about alcohol consumption, obesity, and tobacco use was a major limitation.

The clinical profile and pathophysiology of atrial fibrillation: relationships among clinical features, epidemiology, and mechanisms

Atrial fibrillation (AF) is the most common arrhythmia (estimated lifetime risk, 22%-26%). The aim of this article is to review the clinical epidemiological features of AF and to relate them to underlying mechanisms. Long-established risk factors for AF include aging, male sex, hypertension, valve disease, left ventricular dysfunction, obesity, and alcohol consumption. Emerging risk factors include prehypertension, increased pulse pressure, obstructive sleep apnea, high-level physical training, diastolic dysfunction, predisposing gene variants, hypertrophic cardiomyopathy, and congenital heart disease. Potential risk factors are coronary artery disease, kidney disease, systemic inflammation, pericardial fat, and tobacco use. AF has substantial population health consequences, including impaired quality of life, increased hospitalization rates, stroke occurrence, and increased medical costs. The pathophysiology of AF centers around 4 general types of disturbances that promote ectopic firing and reentrant mechanisms, and include the following: (1) ion channel dysfunction, (2) Ca(2+)-handling abnormalities, (3) structural remodeling, and (4) autonomic neural dysregulation. Aging, hypertension, valve disease, heart failure, myocardial infarction, obesity, smoking, diabetes mellitus, thyroid dysfunction, and endurance exercise training all cause structural remodeling. Heart failure and prior atrial infarction also cause Ca(2+)-handling abnormalities that lead to focal ectopic firing via delayed afterdepolarizations/triggered activity. Neural dysregulation is central to atrial arrhythmogenesis associated with endurance exercise training and occlusive coronary artery disease. Monogenic causes of AF typically promote the arrhythmia via ion channel dysfunction, but the mechanisms of the more common polygenic risk factors are still poorly understood and under intense investigation. Better recognition of the clinical epidemiology of AF, as well as an improved appreciation of the underlying mechanisms, is needed to develop improved methods for AF prevention and management.

Atrial Fibrillation in Acute Coronary Syndrome

Atrial fibrillation (AF) is a common cardiac arrhythmia occurring in an estimated 2.7 to 6.1 million people in the United States. The risk factors for the development of AF are very similar to those for developing coronary artery disease, and AF is often associated with acute coronary syndrome (ACS) and acute myocardial infarction (MI). Overall, AF complicates approximately 10% of acute infarcts and the incidence rate is comparable between the thrombolytic and percutaneous coronary intervention (PCI) eras. Prior to widespread use of thrombolysis, the incidence of AF during acute MI was as high as 18%. Moreover, AF is a marker for increased long term mortality post infarct. Over the past 20 years, the relative mortality risk for patients with AF post MI has remained around 2.5 times that for patients without AF. The treatment of AF in the setting of MI and ACS is similar to without; however there is often an increased urgency to limiting rapid heart rates which may exacerbate acute ischemia. Cardioversion and IV amiodarone may be utilized more liberally in this setting than otherwise. Anticoagulation is usually required both for the treatment of MI and possible PCI, as well as for cerebral vascular accident prevention from AF-induced thromboembolism. Often patients require triple-therapy for optimal treatment of both conditions, and special considerations for bleeding risk must be analyzed.

Non-invasive computed tomography coronary angiography as a gatekeeper for invasive coronary angiography

To determine the rate of subsequent invasive coronary angiography (ICA) and revascularization in relation to computed tomography coronary angiography (CTA) results. In addition, independent determinants of subsequent ICA and revascularization were evaluated. CTA studies were performed using a 64-row (n = 413) or 320-row (n = 224) multidetector scanner. The presence and severity of CAD were determined on CTA. Following CTA, patients were followed up for 1 year for the occurrence of ICA and revascularization. A total of 637 patients (296 male, 56 ± 12 years) were enrolled and 578 CTA investigations were available for analysis. In patients with significant CAD on CTA, subsequent ICA rate was 76%. Among patients with non-significant CAD on CTA, subsequent ICA rate was 20% and among patients with normal CTA results, subsequent ICA rate was 5.7% (p < 0.001). Of patients with significant CAD on CTA, revascularization rate was 47%, as compared to a revascularization rate of 0.6% in patients with non-significant CAD on CTA and no revascularizations in patients with a normal CTA results (p < 0.001). Significant CAD on CTA and significant three-vessel or left main disease on CTA were identified as the strongest independent predictors of ICA and revascularization. CTA results are strong and independent determinants of subsequent ICA and revascularization. Consequently, CTA has the potential to serve as a gatekeeper for ICA to identify patients who are most likely to benefit from revascularization and exclude patients who can safely avoid ICA.