Frequency Of Cardiac Events Research Articles

Intravenous nicorandil in conjunction with coronary reperfusion therapy is associated with better clinical and functional outcomes in patients with acute myocardial infarction.

The aim of this retrospective study was to assess whether intravenous nicorandil, a hybrid of NO and a KATP channel opener, in conjunction with percutaneous coronary intervention (PCI) improves the long-term prognosis in patients with acute myocardial infarction (AMI). Intravenous nicorandil has already been shown to improve the in-hospital prognosis of patients with anterior AMI. The study population consisted of 272 patients with a reperfused AMI who were admitted during a similar time interval, before (control; n=114) and after nicorandil treatment (n=158). In the nicorandil group, a 4 mg bolus injection was given, followed by 6 mg/h infusion for 24 h and then oral nicorandil at 15 mg/day for at least 1 month. In the patients with an anterior AMI, left ventricular (LV) function was better and the frequency of LV remodeling was lower after 3 months in the nicorandil group; however, in those with a non-anterior AMI, there were no differences in functional outcome and the frequency of LV remodeling between the 2 groups. The frequency of cardiac events was significantly lower in the nicorandil group, and the use of nicorandil was derived as a potential factor related to freedom from cardiac events (p<0.01, odds ratio = 0.27). Nicorandil treatment was associated with better myocardial perfusion and a better functional and clinical outcome than PCI alone, and this beneficial effect was maintained for a long time, particularly in patients with anterior AMI.

Effects of Policosanol on Lipid Profile and Cardiac Events in Older Hypercholesterolaemic Patients with Coronary Disease

This study was undertaken to investigate the effects of policosanol administered for 1 year on the lipid profile and cardiac events of older hyper-cholesterolaemic patients with coronary heart disease (CHD). 280 older patients of both sexes with type II hypercholesterolaemia and CHD were included. Patients were randomised after 6 weeks of a standard step I cholesterol-lowering diet to treatment with policosanol (5mg) or placebo tablets once daily for 1 year. The starting dose was 5 mg/day, which was doubled to 10 mg/day if predefined goals were not reached after 6 months on therapy. Cardiac events were defined as death from cardiovascular causes [fatal myocardial infarction (MI), sudden cardiac death] and nonfatal MI, unstable angina pectoris or coronary surgery. Policosanol significantly (p < 0.00001) lowered serum low-density lipoprotein-cholesterol (LDL-C) [21.3%], total cholesterol (TC) [15.9%], TC to high-density lipoprotein-cholesterol (HDL-C) ratio [22.7%] and LDL-C/HDL-C ratio (26.1%), as well as triglycerides (7.8%, p < 0.001). HDL-C was significantly increased (18.2%, p < 0.001). The frequency of cardiac events was lower (p < 0.001) in policosanol (1 event, 0.7%) than in placebo (11 events, 7.9%) recipients. Likewise, the frequency of all vascular serious adverse events (four events, 2.9%) and all-cause hospitalisations in the policosanol group (five events, 3.6%) was lower (p < 0.001) than in the placebo group (15 and 20 events, 10.7 and 14.3%, respectively). No patient died during the study. Policosanol was well tolerated. Long-term policosanol is effective in lowering LDL-C and TC and in increasing HDL-C levels in older patients with CHD, and also showed benefits in the occurrence of cardiac events and overall frequency of serious adverse events of vascular aetiology.

Variable expression of long QT syndrome among gene carriers from families with five different HERG mutations.

This study assessed the phenotypic variability of LQTS in carriers with the same and with different mutations in the LQT2 gene. Mutations of ion-channel genes are known to cause the long QT syndrome (LQTS), a disorder associated with distinctive genotypic-specific electrocardiographic patterns and variable clinical expression. Clinical and electrocardiographic characteristics were assessed in five large LQTS families, each with a different mutation of the HERG gene (LQT2; n = 469, 69% genotyped, 102 carriers). One mutation was located on the N-terminus and the other four on the C-terminus of the HERG channel protein. The QTc duration and the frequency of cardiac events (syncope and LQTS-related cardiac arrest/death) were similar among carriers with the five HERG mutations. QTc was as variable in carriers of the same mutation as it was among carriers with different HERG mutations (P = 0.19). Qualitative assessment of the electrocardiograms revealed extensive intra-and interfamilial variability in T-wave morphology. Among carriers with multiple electrocardiograms extending over 2 to 7 years, variation in QTc over time was minimal. A strong association was found between QTc and the occurrence of cardiac events in carriers of all five mutations. The clinical expression of LQTS was equally variable in carriers from families with the same or different HERG mutations. These findings highlight the complexity of the clinical phenotype in this Mendelian dominant disorder and suggest that one or more modifier genes contribute to the variable expression of this syndrome.

Prognostic Role of On-Line Vectorcardiography as Regards Repeat Revascularization after Successful Coronary Angioplasty

This study evaluated the prognostic significance of continuous on-line vectorcardiography (VCG) during elective coronary angioplasty (percutaneous transluminal coronary angioplasty, PTCA). Patients (n = 192, mean age 58 ± 10), treated with elective and initially successful PTCA, were included. VCG monitoring was started before start of the PTCA procedure and was carried out during the entire procedure. ST vector magnitude (ST-VM) was monitored. A 6-month follow-up was obtained. Main outcome measures were the frequency of cardiac events and revascularization during follow-up. During follow-up, 1 patient died, 6 suffered a nonfatal myocardial infarction and 50 were revascularized. Angiography revealed restenosis in 88% of the patients who had a revascularization. In the total patient group, the VCG predictor of revascularization was the total ischemic time of all ST-VM episodes (p = 0.05). Clinical predictors of revascularization were diabetes mellitus (p < 0.01), a more severe type of lesion (type B; p < 0.01), percent post-PTCA stenosis (p < 0.05), nominal balloon size (p < 0.01), maximum balloon pressure (p < 0.05) and no stent implanted (p < 0.001). In a multivariate analysis all the above significant univariate variables of revascularization were entered. Total ischemic time of ST-VM (p < 0.01) was the best variable giving independent prognostic information. In the nonstent group, total ischemic time of ST-VM (p < 0.01) was the only independent predictor of a further revascularization. In conclusion, VCG monitoring during elective PTCA gives on-line information that identifies patients at an increased risk of a revascularization during 6 months after the initial procedure.

Efficacy and Cardiac Safety of Propiverine in Elderly Patients – A Double–Blind, Placebo–Controlled Clinical Study

The study investigated the efficacy and cardiac safety of propiverine in the elderly, because the induction of life–threatening ventricular arrhythmia has been reported for some drugs prescribed in the therapy of urinary incontinence. Ninety–eight patients (21 male, 77 female; 67.7±6.3 years of age) suffering from urgency, urge incontinence or mixed urge–stress incontinence were included in the double–blind, multicentre, placebo–controlled, randomized study. After a 2–week placebo run–in period, the patients received propiverine (15 mg t.i.d.) or placebo (t.i.d.) for 4 weeks. Before (V1, V2) and during the treatment period (V3, V4), standard ECGs and 24–hour long–term ECGs were recorded. Propiverine caused a significant reduction of the micturition frequency (V2: 8.7±4.2, V4: 6.5±3.2 ml; p≤0.01), reflected in a significant increase in the average micturition volume (V2: 163.5±65.9, V4: 216.3±101.5 ml; p≤0.01) and a significant decrease in episodes of incontinence (–54%; p = 0.048). These findings were confirmed by the overall assessment at V4, in which approximately 90% of patients under propiverine either had no urge incontinence or urge symptoms, or showed improvement. Resting and ambulatory electrocardiograms indicated no significant changes. Neither the frequency–corrected Q–T interval nor other cardiac parameters were relevantly altered. The frequency of cardiac events (Lown classes IVa/b) was random, revealing no difference between placebo and propiverine. The incidence of adverse events was very low (2% dryness of the mouth under propiverine) and confirmed by the findings from the quality of life questionnaires. A favourable benefit–risk ratio without the induction of any cardiac arrhythmia in the treatment of elderly patients suffering from urgency, urge incontinence or combined urge–stress incontinence is therefore proven for propiverine.

Cardiovascular complications in patients with massive middle cerebral artery infarction

P242 Background: Patients with cerebral infarction have a high frequency of underlying cardiac diseases. Acute cardiac events may be observed in patients with massive middle cerebral artery (MCA) infarction due to the severity of neurological insult. We performed this study to determine the frequency of acute cardiac events in this patient population and their impact on outcome and management. Methods: Patients with massive MCA infarction were identified at five university affiliated medical centers using ICD-9 codes or local stroke registries. The medical and neuroimaging records were reviewed at each center by a neurointensivist or stroke neurologist. Only patients who underwent neurological deterioration, defined as a decline in Glasgow Coma Scale (GCS) score of ≥2, attributable to cerebral edema were included. All cardiac events and treatment required during hospitalization were recorded. Outcome was determined at 1 month using Glasgow outcome scores and modified Rankin scale. Results: A total of 54 patients (mean age 62.5±18.0 years; 26 were men) were studied. Underlying cardiac diseases included myocardial infarction (24%), congestive heart failure (20%), and dysrythmias (24%). A total of 16 patients had new cardiac events during hospitalization. These included atrial fibrillation (n=8), atrial flutter (n=1), ventricular fibrillation (n=1), ventricular tachycardia (n=2), myocardial infarction (n=2), and pulmonary edema (n=5); 3 patients had more than one event. Treatment was required for 10 of 16 (62%) events; 3 (19%) were fatal. Overall mortality was higher in patients who developed acute cardiac events during hospitalization (69%) compared to those who did not (40%, p Conclusions: Our study demonstrates the relatively high frequency of acute cardiac events in patients with massive MCA infarction and their impact on outcome. Patients with massive MCA infarctions should be managed in settings suited for effective monitoring and management of cardiovascular emergencies.

Influence of the genotype on the clinical course of the long-QT syndrome. International Long-QT Syndrome Registry Research Group.

The congenital long-QT syndrome, caused by mutations in cardiac potassium-channel genes (KVLQT1 at the LQT1 locus and HERG at the LQT2 locus) and the sodium-channel gene (SCN5A at the LQT3 locus), has distinct repolarization patterns on electrocardiography, but it is not known whether the genotype influences the clinical course of the disease. We determined the genotypes of 541 of 1378 members of 38 families enrolled in the International Long-QT Syndrome Registry: 112 had mutations at the LQT1 locus, 72 had mutations at the LQT2 locus, and 62 had mutations at the LQT3 locus. We determined the cumulative probability and lethality of cardiac events (syncope, aborted cardiac arrest, or sudden death) occurring from birth through the age of 40 years according to genotype in the 246 gene carriers and in all 1378 members of the families studied. The frequency of cardiac events was higher among subjects with mutations at the LQT1 locus (63 percent) or the LQT2 locus (46 percent) than among subjects with mutations at the LQT3 locus (18 percent) (P<0.001 for the comparison of all three groups). In a multivariate Cox analysis, the genotype and the QT interval corrected for heart rate were significant independent predictors of a first cardiac event. The cumulative mortality through the age of 40 among members of the three groups of families studied was similar; however, the likelihood of dying during a cardiac event was significantly higher (P<0.001) among families with mutations at the LQT3 locus (20 percent) than among those with mutations at the LQT1 locus (4 percent) or the LQT2 locus (4 percent). The genotype of the long-QT syndrome influences the clinical course. The risk of cardiac events is significantly higher among subjects with mutations at the LQT1 or LQT2 locus than among those with mutations at the LQT3 locus. Although cumulative mortality is similar regardless of the genotype, the percentage of cardiac events that are lethal is significantly higher in families with mutations at the LQT3 locus.

Antithrombotic therapy after intracoronary stenting.

Conventional percutaneous transluminal coronary angioplasty may result in complications such as abrupt closure and late restenosis. This has led to increased application of mechanical revascularization techniques including intracoronary stents. In the past, subacute thrombosis after intracoronary stenting mandated anticoagulation with warfarin for a minimum of 1 month, with aspirin (ASA) started before the procedure and continued indefinitely. New information suggests that high-pressure balloon inflation, with or without intracoronary ultrasound guidance to ensure successful stent placement, may permit reduction in the antithrombotic regimen to ASA, continued indefinitely, and ticlopidine, continued for 1-3 months. However, the majority of trials supporting this practice are primarily small, nonrandomized, observational studies. One randomized study found a lower frequency of cardiac events, including thrombosis, as well as fewer bleeding complications with combined antiplatelet therapy with ticlopidine compared with anticoagulant therapy with phenprocoumon. Intracoronary stenting without anticoagulation, would permit shorter hospitalization and lead to cost-savings. This has led many cardiologists to administer ASA and ticlopidine without benefit of data from randomized, blinded clinical trials. Antithrombotic therapy after coronary artery stenting is in an evolutionary stage, and additional information regarding the safety and efficacy of ASA and ticlopidine is necessary.

Evolving role of calcium channel blockers in heart failure.

Calcium channel blockers are theoretically effective in the treatment of chronic systolic heart failure because of their actions as arteriolar dilators, antiischemic agents, and relaxants of diastolic left ventricular function, and because they may prevent progression of myocardial dysfunction. The first-generation calcium channel blockers nifedipine, verapamil, and diltiazem cause hemodynamic and clinical deterioration and may increase the frequency of cardiac events in postmyocardial infarction patients with heart failure. These drugs depress left ventricular contractility in the short term, and can activate neurohormonal systems due to their hypotensive effects. The second-generation calcium channel blocker felodipine does not activate the sympathetic nervous and renin-angiotensin systems, but has no effect on exercise capacity or mortality. Amlodipine increases exercise time and reduces symptoms and plasma norepinephrine concentration in heart failure. It also reduces morbidity and mortality in New York Heart Association class i.v. patients with nonischemic dilated cardiomyopathy, and appears to be effective as primary therapy for patients with dilated cardiomyopathy.

Seven-year prognostic value of the electrocardiogram at rest and an exercise test in patients admitted for, but without, confirmed myocardial infarction.

The seven-year prognosis for cardiac events (non-fatal acute myocardial infarction (AMI) or cardiac death) following discharge was related to an electrocardiogram (ECG) at rest and a symptom-limited exercise test in 217 patients admitted with chest pain without confirmed AMI. The follow-up time was 86-98 months, median 88 months. Although the 7-year prognosis was better than in a comparable group of patients with AMI (P < 0.0001), the frequency of cardiac events was still very high. Patients with negative T waves, ST depression or elevation, intraventricular block or Q waves at rest, ST abnormalities during exercise or both constituted a high-risk group. In patients without these ECG abnormalities the prognosis was significantly better (P << 0.0001). The percentages without cardiac events after 7 years were 53 and 92 respectively. Patients with a low rise in the rate-pressure product indicative of decreased function of the left ventricle and patients who developed angina pectoris during exercise also had a significantly impaired 7-year prognosis. This non-invasive approach to risk stratification identified a group of non-AMI patients with a high risk for cardiac events, and a group comprising more than 50% of the patients with a very low risk.

Comparative Prognostic Value of Dipyridamole-Thallium-201 Myocardial Perfusion Imaging 1-4 Days after Myocardial Infarction versus Routine Predischarge Submaximal Exercise Testing

We have previously demonstrated that infarct zone thallium-201 redistribution on dipyridamole-thallium-201 imaging performed 1-4 days after infarction predicts in-hospital and late cardiac events. The present study compared the prognostic value of 1- to 4-day postinfarction dipyridamole-thallium-201 imaging to routine predischarge submaximal exercise electrocardiography in 45 patients. Infarct zone thallium-201 redistribution was present in 14 patients. One patient had redistribution both outside and within the infarct zone. Submaximal exercise electrocardiography was positive for ischemia in 5 patients. The frequency of positive stress test results was significantly lower than infarct zone thallium-201 redistribution (p < 0.05). Cardiac events occurred in 5 patients during a 28 (± 1 l)-month follow-up: 1 cardiac death, 1 nonfatal myocardial infarction, 3 unstable angina requiring emergent revascularization. Cardiac events occurred more frequently in patients with infarct zone thallium-201 redistribution (5/14; 36%) than in patients without redistribution (0/31; p < 0.005). The frequency of cardiac events in patients with positive submaximal exercise electrocardiography (0/5) was not significantly different compared to that in patients with negative tests (5/40; 13%). The sensitivity for detecting patients at risk for late cardiac events was greater with the early dipyridamole-thallium-201 imaging (5/5) than with predischarge submaximal exercise testing (0/5; p < 0.01). Thus, dipyridamole-thallium- 201 myocardial imaging appears to be superior to submaximal exercise electrocardiography for risk stratification after myocardial infarction, not only because it can be applied earlier in hospitalization to allow earlier management decisions, but also because it has greater sensitivity and predictive value for identifying patients at risk for future late cardiac events.

Results of supraceliac aortic clamping in the difficult elective resection of infrarenal abdominal aortic aneurysm

We have used clamping of the aorta above the celiac axis (SC) in 30 of 431 elective resections of infrainguinal abdominal aortic aneurysms (AAA) during the past five years as an alternative to a difficult aortic cuff dissection. The results of SC clamping in these 30 patients are compared with the results of 379 routine aneurysm resections with infrarenal (IR) clamping and 22 additional aneurysm resections where the clamp was placed immediately above the renal arteries. These difficult cuff dissections occurred in 12 patients with inflammatory AAA, in 11 patients with juxtarenal AAA, and in seven patients with recurrent or noninfected false AAA of the proximal cuff. Patients with ruptured or suprarenal aneurysms and those undergoing combined operation for a visceral ischemic syndrome and an aneurysm were excluded from this study. Patients with SC clamping had similar operative mortality rates, comparable renal function, and frequency of cardiac events as patients with IR clamping. Blood loss was slightly higher in the SC group (p = 0.07) and serum aspartate amino transferase (AST) levels were three times higher than in the IR group; however, this was of no clinical significance. In contrast, those 22 patients whose aortas were clamped immediately above the renal arteries (AR) had higher perioperative mortality rates (2% IR, 3% SC vs 32% AR) and a higher incidence of kidney failure requiring dialysis (1% IR, 3% SC vs 23% AR). The mean values of serum creatinine and blood urea nitrogen were also significantly higher in the AR group when compared with both the IR and the SC groups (IR: 25 and 1.5 mg/dl, respectively; SC: 27 and 1.8 mg/dl; AR: 41 and 3.5 mg/dl). The single most important risk factor accounting for the differences between clamping above the celiac artery and clamping above the renal arteries was the presence of atherosclerotic debris in the non-aneurysmal, juxtarenal aortic segment. Clamping the aorta with juxtarenal atherosclerosis caused either atheroembolization to kidneys, legs, and intestine or injury to the aorta, renal arteries, or both; it was the cause of morbidity in all five cases of kidney failure requiring dialysis and accounted for all seven of the deaths in the AR group. SC clamping does not add risk to the patient undergoing resection of an infrarenal AAA and is the preferred method of achieving proximal control of the infrarenal aorta when a hazardous cuff dissection is likely.