The prognostic implications of lack of palpitations in patients hospitalised with atrial fibrillation: observations from a 20-year registry

OBJECTIVES

It is well recognised that patients differ in the clinical presentation of atrial fibrillation (AF), ranging from the typical symptom of palpitations, atypical symptoms in others and a substantial that are asymptomatic. Whether the different patterns of presentation are associated with differences in outcomes is not known. The aim of this study was to evaluate the prevalence and the prognostic implications of lack of palpitations among patients hospitalised with AF in a large prospective registry.

METHODS

Retrospective analysis of all patients hospitalised with AF in Qatar from 1991 to 2010 was made. Patients were divided into two groups according to the presence or absence of palpitations on presentation. Clinical characteristics and outcome were analysed.

RESULTS

During the 20-year period, 3850 patients were hospitalised for AF; 1724 (44.8%) had palpitations on presentation while 2126 (55.2%) had no palpitations. Patients who lacked palpitations were 9 years older, had a higher prevalence of diabetes mellitus (64.7% vs. 35.3%), underlying coronary artery disease (CAD; 14.6% vs. 6.2%) and severe left ventricular dysfunction on echocardiography (25.5% vs. 6.6%), (all, p = 0.001). There were 141 deaths among the group with no palpitations compared with 19 among the group with palpitations (6.6% vs. 1.1%). Multivariate analysis of mortality predictors identified 'lack of palpitations' as an independent predictor of in-hospital mortality (relative risk 5.56; 95% confidence interval 1.20-25.0, p = 0.03).

CONCLUSIONS

Our study demonstrates for the first time that lack of palpitations as the presenting symptom of patients with AF is associated with worse in-hospital outcome independent of other risk factors or therapy. The underlying mechanisms and the role of confounders warrant further investigation.

Anti-Arrhythmic Agents in the Treatment of Atrial Fibrillation

Although atrial fibrillation (AF) is the most common sustained arrhythmia seen during daily cardiovascular physician practice, its management remained a challenge for cardiology physician as there was no single anti-arrhythmic agents proved to be effective in converting atrial fibrillation and kept its effectiveness in maintaining sinus rhythm over long term. Moreover all the anti-arrhythmic agents that are used in treatment of AF were potentially pro-arrhythmic especially in patients with coronary artery disease and structurally abnormal heart. Some of these drugs also have serious non cardiac side effects that limit its long term use in the management of atrial fibrillation. Several new and investigational anti-arrhythmic agents are emerging but data supporting their effectiveness and safety are still limited. In this systematic review we examine the efficacy and safety of these medications supported by the major published randomized trials, meta-analyses and review articles and conclude with a summary of guidelines recommendations.

Atrial fibrillation in Middle Eastern Arab and South Asian patients hospitalized with acute myocardial infarction: experience from a 20-year registry in qatar (1991-2010)

BACKGROUND

Recent evidence suggests that there are ethnic variations in atrial fibrillation (AF) susceptibility and incidence following acute myocardial infarction (AMI).

OBJECTIVES

The aim of this study was to evaluate the incidence and predictors of AF in the setting of AMI in Middle Eastern Arab and South Asian patients and its impact on in-hospital morbidity and mortality.

METHODS

A retrospective analysis of a prospective registry of all patients hospitalized with AMI in the state of Qatar from 1991 through 2010 was made. Clinical characteristics and outcomes of AMI patients with and without AF were compared. Sub-analysis according to ethnicity was also performed.

RESULTS

During the 20-year period; a total of 12,881 patients were hospitalized with AMI. Of these 5028 were Arabs and 5985 were South Asians. A total of 227 had AF during hospitalization with an overall incidence of 1.8% (156 Arabs; incidence 3.1% and 48 South Asians; incidence 0.8%). The mean age of AF patients was 65 years (Arabs 69, South Asians 54). Patients with AF were significantly older and had more cardiovascular co-morbidities than patients without AF, and were more likely to have non-ST elevation AMI on presentation. Patients with AF had significantly higher in-hospital mortality rate (20.3% versus 7.1%; P=0.001) and stroke rates (1.8% versus 0.3%; P=0.001) when compared to patients without AF. Age was the only independent predictor of AF development in patients with AMI in our study.

CONCLUSIONS

Our study reports variability in the prevalence of AF among AMI patients according to ethnicity using a 20-year registry from a Middle Eastern country. Advancing age was the major independent predictor of AF in our AMI patients. Further prospective studies are required evaluating optimal therapeutic approaches for these high-risk patients in order to reduce the high mortality observed.

Impact of religious Ramadan fasting on cardiovascular disease: a systematic review of the literature

BACKGROUND

Fasting during the month of Ramadan is a religious obligation that is practiced by millions of people around the world yet there is no clear scientific consensus on its effects on cardiovascular disease. This study was performed to inform physicians as well as patients of evidence based recommendations on this subject.

AIM

The study was undertaken to assess: (1) any alteration in the incidence of acute cardiac illness during Ramadan fasting; (2) whether fasting during the month of Ramadan alters the clinical status of patients with stable cardiac disease; and (3) the impact of Ramadan fasting on cardiovascular risk factors in normal subjects, in patients with stable cardiac disease, metabolic syndrome, dyslipidemia, type 2 diabetes and systemic hypertension.

STUDY DESIGN

Systematic review of the literature.

METHOD

A Medline search of the English literature published between January 1980 and September 2012.

RESULTS

The incidence of acute cardiac illness during Ramadan fasting was similar to non-fasting days, although the timing of symptom onset may be different, with significant increase in events during the period of 'breaking fast' when compared to non-fasting days. The majority of patients with stable cardiac illness can undergo Ramadan fasting without any clinical deterioration. Body mass index, lipid profile, and blood pressure showed significant improvement in normal healthy subjects, patients with stable cardiac illness, metabolic syndrome, dyslipidemia and hypertension during Ramadan fasting. The lipid profile of diabetic patients deteriorated significantly during Ramadan fasting.

CONCLUSIONS

Ramadan fasting is not associated with any change in incidence of acute cardiac illness and the majority of cardiac patients can fast without any difficulty. Improvement in lipid profile, especially 30% to 40% increment in high-density lipoprotein, as reported in some studies, appear promising. Diabetic patients should be carefully monitored during Ramadan fasting.

Effect of age on treatment, trends and outcome of patients hospitalized with atrial fibrillation: insights from a 20-years registry in a Middle-Eastern country (1991-2010)

BACKGROUND

Most studies on atrial fibrillation (AF) epidemiology, treatment, and outcomes have included mainly Caucasians patients. The world literature on AF in other ethnicities is very limited particularly in the elderly.

AIMS

The aim of this study was to compare the clinical characteristics, treatment and outcome of elderly and younger patients hospitalized with AF in a Middle-Eastern country and examine the trends of AF etiologies over a 20-year period.

METHODS

A retrospective analysis of a prospective registry of all patients hospitalized with AF in Qatar from 1991 through 2010 was made. Patients were divided into three groups; group 1: patients ≤50 years old, group 2: patients between 51 and 70 years old, and group 3: patients >70 years old. Clinical characteristics, management, and outcomes of AF patients were compared according to age.

RESULTS

Between the year 1991 and the end of 2010, a total 3848 consecutive patients were admitted with AF. One thousand three hundred and forty-five patients were ≤50 years, 1759 were between 51 and 70 years and 744 patients were >70 years old. Elderly patients were more likely to have hypertension and chronic renal impairment. There was a higher prevalence of associated coronary artery disease and aortic stenosis in elderly patients with a lower left ventricular ejection fraction than the younger age groups. A lower use of anticoagulation in the elderly group was observed but there was no underuse of other evidence-based medications. The older AF patients had significantly higher in-hospital mortality and stroke rates with no significant changes in mortality trends over the 20 years of study. An increasing trend of the associated acute coronary syndromes, hypertension and diabetes mellitus prevalence was observed in the elderly group.

CONCLUSION

Anticoagulation remains underutilized in elderly patients with AF despite proven efficacy and increasing trends of cardiovascular comorbidities. The current study underscores the urgent need for prospective studies to investigate warfarin contraindications, relative warfarin efficacy and bleeding risks in our region to help guide healthcare providers in warfarin prescribing in this frail patient population and consequently reduce the risk of AF-related disabling strokes and mortality.

Secular Trends, Treatments, and Outcomes of Middle Eastern Arab and South Asian Patients Hospitalized With Atrial Fibrillation

A prospective registry was made of all patients hospitalized with atrial fibrillation (AF) in the State of Qatar from 1991 to 2010. Clinical characteristics, management, and outcomes were compared according to ethnicity (Middle Eastern Arab vs South Asian). During this 20-year period, 2857 Arabs and 548 Asians were hospitalized for AF. Arabs were 9 years older and more likely to have hypertension, diabetes mellitus (DM), chronic renal impairment, and dyslipidemia than the Asians. Valvular heart disease and acute coronary syndromes were more common among Asians, while congestive heart failure was more common in Arabs. The overall inhospital mortality was lower in Asians than that of Arabs, while stroke rates were comparable. There was an increase in the prevalence of DM and hypertension in both the groups in the latter years of the study period, but there was no change in mortality trends. Our findings underscore the need to study AF according to ethnicity.

Immediate and one-year outcome of patients presenting with acute coronary syndrome complicated by stroke: findings from the 2nd Gulf Registry of Acute Coronary Events (Gulf RACE-2)

Background

Stroke is a potential complication of acute coronary syndrome (ACS). The aim of this study was to identify the prevalence, risk factors predisposing to stroke, in-hospital and 1-year mortality among patients presenting with ACS in the Middle East.

Methods

For a period of 9 months in 2008 to 2009, 7,930 consecutive ACS patients were enrolled from 65 hospitals in 6 Middle East countries.

Results

The prevalence of in-hospital stroke following ACS was 0.70%. Most cases were ST segment elevation MI-related (STEMI) and ischemic stroke in nature. Patients with in-hospital stroke were 5 years older than patients without stroke and were more likely to have hypertension (66% vs. 47.6%, P = 0.001). There were no differences between the two groups in regards to gender, other cardiovascular risk factors, or prior cardiovascular disease. Patients with stroke were more likely to present with atypical symptoms, advanced Killip class and less likely to be treated with evidence-based therapies. Independent predictors of stroke were hypertension, advanced killip class, ACS type –STEMI and cardiogenic shock. Stroke was associated with increased risk of in-hospital (39.3% vs. 4.3%) and one-year mortality (52% vs. 12.3%).

Conclusion

There is low incidence of in-hospital stroke in Middle-Eastern patients presenting with ACS but with very high in-hospital and one-year mortality rates. Stroke patients were less likely to be appropriately treated with evidence-based therapy. Future work should be focused on reducing the risk and improving the outcome of this devastating complication.

The therapeutic potential of PCSK9 inhibition in primary dyslipidemia, the example from SAR236553/REGN727

The proprotein convertase subtilisin kexin 9 (PCSK9) is a serine protease that has recently emerged as a potential target for the treatment of hypercholesterolemia. SAR236553/REGN727 is a highly specific monoclonal antibody to PCSK9 that significantly reduced LDL cholesterol levels in healthy volunteers and in subjects with hypercholesterolemia in three Phase-I studies. It was subsequently tested in a recent Phase-II study in patients with primary hypercholesterolemia with impressive results. In this report the trial is discussed along with the significance of the results in guiding further research in PCSK9 inhibition.

Contrast-enhanced 64-Section Coronary Multidetector CT Angiography versus Conventional Coronary Angiography for Stent Assessment

PURPOSE

To prospectively evaluate the accuracy of 64-section computed tomography (CT) for diagnosis of stent restenosis, by using conventional coronary angiography as the reference standard.

MATERIALS AND METHODS

The ethics committee granted permission for the study; patients gave written consent. Contrast material-enhanced coronary CT angiography was performed in 53 patients (45 men, eight women; mean age, 54 years +/- 9 [standard deviation]) suspected of having stent restenosis. Coronary CT angiographic findings were compared with conventional coronary angiographic findings. Two physicians analyzed coronary CT angiographic data sets with multiplanar reformatted images and three-dimensional reformations by using a volume-rendering technique and looked for stent detectability, low-attenuation in-stent filling defects, and grades of restenosis. Conventional coronary angiographic results were interpreted by one of several observers in consensus for stent restenosis; they were blinded to coronary CT angiographic data. Statistical software and general estimating equations were used for data analysis.

RESULTS

One hundred ten stents were identified in 53 patients. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of coronary CT angiography in detection of in-stent restenosis were 96.9%, 88.0%, 77.5%, 98.5%, and 91%, respectively. Coronary CT angiography depicted in-stent low-attenuation filling defects with an accuracy of 91% and negative predictive value of 98.5% (95% confidence interval: 90.9, 99.9). Coronary CT angiography depicted the status of 97 of 107 stents. There was no significant difference between in-stent lumen visibility and stent diameter (P = .104). Coronary CT angiography helped diagnose 15 of 18 stent restenoses with less than 50% narrowing, five of five stent restenoses with 50%-74% narrowing, and nine of nine (100%) stent restenoses with 75% or greater narrowing or total occlusion of the stent lumen.

CONCLUSION

Coronary CT angiography can depict in-stent low-attenuation filling defects, which appear to be a reliable sign of stent restenosis, and 64-section CT depicts such defects with a high degree of accuracy.

Drug-Eluting Coronary Stents

The introduction and widespread use of coronary stents have been the most important advancement in the percutaneous treatment of coronary artery disease since the introduction of balloon angioplasty. Coronary artery stents reduce the rate of angiographic and clinical restenosis compared to balloon angioplasty. This angiographic restenosis was further reduced with the introduction of drug-eluting stents and hence further reduction in the frequency of major adverse cardiac events. Herein we present a comprehensive and up-to-date review about the use of drug-eluting stents in the treatment of coronary artery disease.

Selected highlights from the 54th annual scientific session of the American College of Cardiology, Orlando, USA, 6-9 March 2005

The recent scientific session of the American College of Cardiology, held in Orlando, Florida, US, was one of the largest gatherings in the field of cardiovascular medicine worldwide. This year's session provided a wealth of new information in many areas of cardiovascular medicine and the results of several clinically relevant new trials and current challenges facing cardiology were presented. Provided here are selected highlights that have important implications for clinical practice.

The therapeutic potential of vasopressin receptor antagonists in congestive heart failure

Hospitalisation of patients presenting with deteriorating congestive heart failure is occurring with increasing frequency and is associated with significant morbidity and mortality. Diuretic use, the mainstay therapy for congestion, is associated with electrolyte abnormalities and deteriorating renal function. In a recent randomised study, tolvaptan, a novel vasopressin antagonist, in addition to standard therapy including diuretics, increased net fluid loss resulting in decreased body weight more effectively than standard therapy alone in patients hospitalised for heart failure. This desirable effect was achieved without adversely affecting blood pressure, heart rate, electrolyte levels, or renal function. Although tolvaptan did not reduce the rate of deteriorating heart failure after discharge, post hoc analysis suggested that mortality might be reduced in high-risk patients treated with tolvaptan. These results make an important contribution to heart failure research, and offer an insight into the future role of vasopressin antagonism in the treatment of congestive heart failure.

The therapeutic potential of ximelagatran to become the anticoagulant of choice in medicine: a review of recently completed clinical trials

Ximelagatran (Exanta, AstraZeneca) is a novel oral direct thrombin inhibitor that inhibits the final step in the coagulation process - namely, the conversion of fibrinogen to insoluble fibrin by thrombin. Recently completed large clinical trials have evaluated the efficacy and safety of ximelagatran compared to standard anticoagulation therapy with warfarin and heparins in several thrombotic disorders including the treatment and prevention of venous thromboembolism following major orthopaedic surgery; stroke prevention in atrial fibrillation; and after acute myocardial infarction. This article reviews these recent clinical trials and explores the therapeutic potential of ximelagatran to become the oral anticoagulant of first choice in medicine.

Intensive lipid-lowering therapy in coronary artery disease: implications of the REVERSAL and PROVE-IT trials

Current international guidelines recommend that the goal of treatment with lipid-lowering therapy in patients with established coronary artery disease (CAD) should be a low-density lipoprotein cholesterol level of < 100 mg/dl. The question that remains to be answered is whether more aggressive lowering of low-density lipoprotein cholesterol levels below this target offers additional benefit and whether it can be tolerated. Two recently published related studies addressed this question by comparing intensive lipid lowering with atorvastatin (Lipitor, Pfizer) 80 mg/day with a moderate lipid-lowering regimen of pravastatin (Pravachol, Bristol-Myers Squibb) 40 mg/day. The first study, the Reversing Atherosclerosis with Aggressive Lipid Lowering (REVERSAL) compared the effect of the two regimens on coronary artery atheroma burden and progression using intravascular ultrasound in patients with symptomatic CAD. The second study, the Pravastatin or Atorvastatin Evaluation and Infection Therapy (PROVE-IT) was a clinical outcome trial in patients recently hospitalised with acute coronary syndromes. This article reviews the implications of these two studies in the management of patients with CAD. In addition, other ongoing trials and future directions are explored.

Lipid-lowering therapy in patients with average cholesterol and high cardiovascular risk, insights from the Heart Protection Study

Although the benefits of cholesterol-lowering with statins has been established for patients with high cholesterol levels as well as for patients with prior occlusive coronary heart disease, substantial uncertainty has existed about the long-term benefits of these agents in particular types of patient, including patients with moderate or low baseline cholesterol levels pre-treatment, women, the elderly, and those with prior occlusive non-coronary vascular disease. The Heart Protection Study was designed to resolve these uncertainties and to provide substantially more safety information of statins. In this report the study is presented with the significance and practical implications of the results briefly discussed.

Impact of coronary artery stents on mortality and nonfatal myocardial infarction: meta-analysis of randomized trials comparing a strategy of routine stenting with that of balloon angioplasty

BACKGROUND

A strategy of routine stenting has been shown to reduce the need for target-vessel revascularization compared with a strategy of balloon angioplasty alone; however, the impact on mortality and frequency of nonfatal myocardial infarction is unclear. The aim of this study was to provide a quantitative comparison of the impact of coronary stenting on the rates of mortality and myocardial infarction with that of balloon angioplasty with provisional stenting.

METHODS

We performed a meta-analysis of randomized trials comparing routine coronary stenting to percutaneous transluminal coronary angioplasty (PTCA), including only those trials that used combination antiplatelet therapy (aspirin and a thienopyridine) as an adjuvant to stenting. Such trials included: the Belegian Netherlands Stent Study (BENESTENT) II, Optimal Coronary Balloon Angioplasty With Provisional Stenting Versus Primary Stent (OCBAS), Balloon Optimization vs Stent Study (BOSS), Evaluation of Platelet IIb/IIIa Inhibitor for Stenting (EPISTENT), Optimum Percutaneous Transluminal Coronary Angioplasty Compared With Routine Stent Strategy (OPUS-1), French Optimal Stenting Trial (FROST), Angioplasty or Stent (AS), and Doppler Endpoint Stenting International Investigation (DESTINI) trials for de novo coronary artery lesions; the Stent vs Percutaneous Angioplasty in Chronic Total Occlusion (SPACTO), Total Occlusion Study of Canada (TOSCA), Stent or Angioplasty after Recanalization of Chronic Coronary Occlusions (SARECCO), and Mayo-Japan Investigation for Chronic Total Occlusion (MAJIC) trials for coronary occlusions; the Primary Angioplasty Versus Stent Implantation in Acute Myocardial Infarction (PASTA), Gianturco-Roubin in Acute Myocardial Infarction (GRAMI), Florence Randomized Elective Stenting in Acute Coronary Occlusions (FRESCO), Immediate Coronary Angioplasty with Elective Wiktor Stent Implantation Compared with Conventional Balloon Angioplasty in Acute Myocardial Infarction (STENTUIM-2), Stent Primary Angioplasty in MI (Stent-PAMI), Zwolle, and Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trials for acute ST-segment elevation myocardial infarction; and the Intracoronary Stenting or Angioplasty for Restenosis Reduction in Small Arteries (ISAR-SMART), Park, Stenting in Small Arteries (SISA), and Bestent in Small Arteries (BESMART) trials for small vessels.

RESULTS

The 23 trials enrolled 10,347 patients, with 5130 patients randomized to receive stent and 5217 patients randomized to receive balloon angioplasty. A total of 902 (17 %) of patients crossed over from a strategy of balloon angioplasty to stent placement because of the inability to achieve a satisfactory result with a balloon. No significant difference was observed between the stent group and PTCA group in the rates of death or myocardial infarction, despite a significant reduction in the frequency of major adverse cardiac events (odds ratio, 0.59; 95% CI, 0.50-0.70; P <.001), which was driven entirely by a reduction in target vessel revascularization.

CONCLUSIONS

An initial strategy of stent placement versus balloon angioplasty with provisional stenting is associated with a similar mortality rate and frequency of nonfatal myocardial infarction after a mean follow-up period of 12.8 months. Patients who underwent stent placement had a significantly lower risk of major adverse cardiac events only when target revascularization is included as an end point.

Angiotensin receptor blockers in acute myocardial infarction

It has been established from multiple randomised, placebo-controlled trials that angiotensin-converting enzyme inhibitors reduce the risk of death and major non-fatal cardiovascular events after acute myocardial infarction, especially when these agents are used for long-term treatment in high-risk patients. Angiotensin receptor blockers represent a theoretically appealing class of drugs for use in combination with or as alternatives to angiotensin-converting enzyme inhibitors in such patients. The Valsartan in Acute Myocardial Infarction (VALIANT) trial compared the effects of valsartan, captopril and the combination of both in a population of high-risk patients with evidence of left ventricular dysfunction after acute myocardial infarction. This article discusses this important study and its implications for the clinical management of these high-risk patients.

Acute myocardial infarction in a professional diver after jellyfish sting

To our knowledge, acute myocardial infarction after jellyfish envenomation has not been reported previously. We describe a previously healthy 45-year-old male diver who had an acute inferior myocardial infarction with right ventricular involvement after a jellyfish sting on his left forearm while diving in the Gulf Sea. The patient had a normal controlled ascent after the incident. He had no risk factors for coronary artery disease, and cardiac catheterization revealed normal coronary arteries. Acute myocardial infarction should be considered in patients who experience chest pain or have hemodynamic compromise after jellyfish envenomation.

Is there a role for oral blockade of platelet glycoprotein IIb/IIIa receptors in coronary and cerebrovascular disease?

The success of intravenous platelet glycoprotein (GP) IIb/IIIa receptor blockers as potent antithrombotic therapies has ignited interest in the research and development of oral agents with the intention of extending the initial clinical benefits proven with intravenous GP IIb/IIIa blockers to long-term care with the use of oral agents. Nonetheless, results of the recently published Blockade of the Glycoprotein IIb/IIIa Receptor to Avoid Vascular Occlusion (BRAVO) trial support the disappointing results of the earlier published studies, which revealed that the use of oral GP IIb/IIIa inhibitors was associated with an unacceptable increased mortality. Further research to elucidate the mechanism of this increased fatality risk is warranted before any further clinical studies with the oral GP IIb/IIIa inhibitors can be ethically justified.