ECG Signs Of Ischemia Research Articles

Quinidine-responsive out-of-hospital polymorphic ventricular tachycardia in patients with coronary heart disease.

We recently reported that patients with coronary artery disease (CAD) who develop polymorphic ventricular tachycardia (VT) during the healing phase of an acute coronary event, generally fail to respond to revascularization or standard antiarrhythmic therapy but respond immediately to quinidine therapy. Here, we describe that CAD patients presenting with out-of-hospital polymorphic VT without a recent coronary event or an obvious precipitating factor, also respond uniquely to quinidine therapy. Retrospective study of patients with unheralded, mainly out-of-hospital, polymorphic VT related to CAD but without evidence of acute myocardial ischaemia. We identified 20 patients who developed polymorphic VT without precipitating factors. The polymorphic VT events were triggered by extrasystoles with short (376 ± 49 ms) coupling interval. Arrhythmic storms occurred in 70% patients. These arrhythmic storms were generally refractory to conventional antiarrhythmic therapy but invariably responded to quinidine therapy. Revascularization was antiarrhythmic in 3 patients despite the absent clinical or ECG signs of ischaemia. During long-term follow-up (range 2 months to 11 years), 3 (15%) of patients not receiving quinidine developed recurrent polymorphic VT. There were no recurrent arrhythmias during long-term quinidine therapy. Patients with CAD may develop polymorphic VT in the absence of obvious acute ischaemia or apparent precipitating factors, presenting as out-of-hospital polymorphic VT with high risk of arrhythmic storms that respond uniquely to quinidine therapy.

Abstract 18710: Added Value of Electrocardiographic Signs and Symptoms to Improve Early Detection of Acute Coronary Syndrome in the Emergency Department

Background: Early identification and diagnosis are critical in the management of patients with acute coronary syndrome (ACS) since time-dependent therapies reduce patient mortality and morbidity. Objective: The aims of this study were to describe differences in presenting symptoms by individual ACS diagnoses and determine the prognostic value of both signs (electrocardiographic evidence of ischemia) and symptoms for an ACS diagnosis. Method: Patients > 21 years old, with any ECG ischemic changes (ST-elevation, ST-depression, T-wave inversion), elevated serum troponin, and ACS symptoms presenting to one of five emergency departments (ED) were eligible for the study. Patients completed the ACS Symptom Checklist, a validated 13-item instrument that measures cardiac symptoms (typical and atypical). Pearson Chi-square tests were used for bivariate analyses and logistic regression was used for multivariate modeling. Results: A total of 1,031 patients (mean age 60 + 14, 62% male, 70% White) were enrolled; 450 (43.7%) were diagnosed with ACS. One hundred eleven (11%) had ST-elevation myocardial infarction (STEMI), 236 (23%) had non-ST elevation myocardial infarction (NSTEMI), 103 (10%) had unstable angina (UA), and 581 (56%) were ruled-out for ACS. Patients with STEMI were more likely to report chest pain, diaphoresis, and higher symptom distress (p<0.05) at presentation than those without. Patients with NSTEMI were more likely to report arm pain and patients with UA were more likely to report lightheadedness (p<0.05). The presence of any chest symptoms (OR 2.24; 95% CI 1.27-3.97), higher symptom distress (OR 1.07; 95% CI 1.0-1.15), and a lower number of symptoms (OR 0.92; 95% CI 0.86-0.98) were independent predictors of an ACS diagnosis (p<0.05). The strongest predictor of an ACS diagnosis was the presence of ECG ischemic changes (OR 4.51, 95% CI 3.20-6.36) adjusting for symptoms, age, gender, heart rate, arrhythmia, and troponin levels (p<0.001). Conclusion: ECG signs of ischemia combined with specific symptom characteristics may enhance timely triage and detection of ACS in the ED. Predictive models that incorporate presenting signs and symptoms should be explored for this vulnerable population.

L-Arginine Attenuates Cardiac Dysfunction, But Further Down-Regulates α-Myosin Heavy Chain Expression in Isoproterenol-Induced Cardiomyopathy.

In view of previously reported increased capacity for nitric oxide production, we suggested that l-arginine (ARG), the nitric oxide synthase (NOS) substrate, supplementation would improve cardiac function in isoproterenol (ISO)-induced heart failure. Male Wistar rats were treated with ISO for 8days (5mg/kg/day, i.p.) or vehicle. ARG was given to control (ARG) and ISO-treated (ISO+ARG) rats in water (0.4g/kg/day). ISO administration was associated with 40% mortality, ventricular hypertrophy, decreased heart rate, left ventricular dysfunction, fibrosis and ECG signs of ischaemia. RT-PCR showed increased mRNA levels of cardiac hypertrophy marker atrial natriuretic peptide, but not BNP, decreased expression of myosin heavy chain isoform MYH6 and unaltered expression of pathological MYH7. ISO increased the protein levels of endothelial nitric oxide synthase, but at the same time it markedly up-regulated mRNA and protein levels of gp91phox, a catalytical subunit of superoxide-producing NADPH oxidase. Fibrosis was markedly increased by ISO. ARG treatment moderately ameliorated left ventricular dysfunction, but was without effect on cardiac hypertrophy and fibrosis. Combination of ISO and ARG led to a decrease in cav-1 expression, a further increase in MYH7 expression and a down-regulation of MYH6 that inversely correlated with gp91phox mRNA levels. Although ARG, at least partially, improved ISO-impaired basal left ventricular systolic function, it failed to reduce cardiac hypertrophy, fibrosis, oxidative stress and mortality. The protection of contractile performance might be related to increased capacity for nitric oxide production and the up-regulation of MYH7 which may compensate for the marked down-regulation of the major MYH6 isoform.

Baseline NT-ProBNP level predicts success of cardioversion of atrial fibrillation with flecainide.

BackgroundPatients with acute-onset symptomatic atrial fibrillation (AF) can be treated with flecainide. However, flecainide may induce arrhythmias and/or exaggerate heart failure. Therefore, validated markers to predict the efficacy of flecainide and prevent adverse effects are required. We hypothesised that lower NT-proBNP plasma levels correlate with higher success rates of cardioversion with flecainide in patients with AF.MethodsIn this prospective single-centre study, we included 112 subsequent patients with acute-onset (< 24 h) symptomatic AF. Patients with symptoms of heart failure and ECG signs of ischaemia were excluded. Baseline laboratory measurements, including NT-proBNP, were done. Echocardiograms were performed ~ 2 weeks after restoration of SR.ResultsCardioversion with flecainide was successful in 91 patients (87 %). NT-proBNP was lower in patients with successful cardioversion (P < 0.001). Logistic regression indicated NT-proBNP as an independent predictor of successful cardioversion. A cut-off NT-proBNP value of 1550 pg/ml provided optimal test accuracy to predict successful cardioversion.ConclusionIn patients with < 24 h of symptomatic AF, NT-proBNP levels up to 1550 pg/ml correlate with high success rates (94 %) of cardioversion with flecainide. Conversely, NT-proBNP higher than 1550 pg/ml correlates with poor success rates (36 %). Further research is needed to validate the predictive value of NT-proBNP for successful cardioversion with flecainide.

Characteristics and outcome among patients who dial for the EMS due to chest pain

ObjectivesThis study aims to describe patients who called for the emergency medical service (EMS) due to chest discomfort, in relation to gender and age. MethodsAll patients who called the emergency dispatch centre of western Sweden due to chest discomfort, between May 2009 and February 2010, were included. Initial evaluation, aetiology and outcome are described as recorded in the databases at the dispatch centre, the EMS systems and hospitals. Patients were divided into the following age groups: ≤50, 51–64 and ≥65years. ResultsIn all, 14,454 cases were enrolled. Equal proportions of men (64%) and women (63%) were given dispatch priority 1. The EMS clinicians gave priority 1 more frequently to men (16% versus 12%) and older individuals (10%, 15% and 14%, respective of age group). Men had a significantly higher frequency of central chest pain (83% versus 81%); circulatory compromise (34% versus 31%); ECG signs of ischaemia (17% versus 11%); a preliminary diagnosis of acute coronary syndrome (40% versus 34%); a final diagnosis of acute myocardial infarction (14% versus 9%) and any potentially life-threatening condition (18% versus 12%). Individuals aged ≥65years were given a lower priority than individuals aged 51–64years, despite poorer characteristics and outcome. In all, 78% of cases with a potentially life-threatening condition and 67% of cases that died within 30days of enrolment received dispatch priority 1. Mortality at one year was 1%, 4% and 18% in each individual age group. ConclusionMen and the elderly were given a disproportionately low priority by the EMS.

The ECG after out-of-hospital cardiac arrest is a reliable tool to guide immediate triage? Analysis of 88 patients matched with acute coronary angiography

Background: In comatose patients resuscitated (ROSC) after out-of-hospital cardiac arrest (OHCA) the ECG is not considered a reliable tool to predict acute coronary-artery occlusion. Thus, immediate coronary angiography (CA) has been suggested for diagnostic and therapeutic purposes. However, CA could delay therapeutic hypothermia (TH), when indicated, and has other logistics drawbacks. Therefore, aim of the study was to evaluate in survivors of OHCA the reliability of ECG to triage to immediate or delayed CA and interventions. Methods: Observational prospective analysis of patients (pts) with ROSC after OHCA admitted alive to the Emergency Room (ER) of a tertiary center from March 27, 2004 to December 31, 2012 treated with TH and undergoing early CA and PCI. Results: We analysed 142 pts patients with ROSC after OHCA, admitted alive to our hospital, that underwent early CA (median age: 66.5 (IQR 55-74) yrs, males: 70%, shockable rhythm: 71%, interval OHCA-resuscitation ≤20 min: 69%) with at least 2 consecutive ECGs post ROSC available. 88 pts fulfilled the study criteria and ECG were analyzed from two different operators. The mean time between ROSC and the first ECG was 5±4 min. 36 pts (41%) meet the ECG criteria for ST elevated myocardial infarction (STEMI, Group A), 28 pts (32%) for subendocardial ischemia (Group B), and in 24 (27%) pts there were no ECG signs of ischemia (Group C). In the Group A at early CA 23 pts (64%) had acute coronary occlusion, 7 pts (19%) subocclusion of at least one vessel, and 6 (17%) 3 vessels disease or no lesions. 30 (83%) pts underwent successful PCI. In the Group B 7 pts (25%) underwent to PCI (1 case 100% acute occlusion of distal right coronary artery and 6 cases of stenosis 70-90%). As opposed in the Group C, no one patient had acute coronary occlusion at CA. Notably, only 1 case in the Group B and 1 case in the Group C developed elevated Troponin I (one case of myocarditis and one case ofhypertrophic cardiomyopathy, respectively). The in-hospital crude mortality of patients was 20% in Group A, 15% in Group B and 22% in Group C; 60% of survivors were discharged with a good neurological outcome. Conclusions: Our preliminary data suggest that a simple ECG after ROSC in OHCA survivors could be a good predictor for acute coronary occlusion. Therefore, ST elevation cases could be triage to immediate CA (Group A), in the presence of ECG ischemia the CA can be considered (Group B), while in the absence of ECG ischemia CA could be delayed (Group C). These findings, if confirmed by adequately sized studies, could simplify the triage of ROSC pts after OHCA to CA.

Place of extracorporeal membrane oxygenation in acute aortic dissection

Coronary artery dissection (CAD) is a rare but serious complication of type A aortic dissection (AD) which may be discovered preoperatively in the presence of clinical or ECG signs of ischemia, or intraoperatively after dissection of the coronary ostium. Treatment of CAD consists of surgical repair with glue and, if necessary, coronary artery bypass graft. No case of AD with CAD complicated by major arrhythmias treated by assisted circulation has been reported in the literature. We report the first case of AD with implementation of extracorporeal membranous oxygenation following cardiotomy with a favorable outcome.

Assessment of the Human Coronary Collateral Circulation

Cardiovascular disease is the leading cause of death in industrialized countries and may become the most important reason for mortality worldwide.1 In patients suffering from coronary artery disease (CAD), the size of myocardial infarction mainly determines outcome.2 Accordingly, the primary strategy to reduce cardiovascular mortality is by shrinking infarct size (IS) (Figure 1A).3 In the clinical setting of acute myocardial infarction, Antoniucci et al4,5 documented in 1164 patients undergoing primary percutaneous coronary intervention (PCI) that the presence of angiographic collaterals before PCI purported a survival benefit compared with the situation without them (Figure 2). As a surrogate for IS, studies on the effect of myocardial salvage procedures have employed the magnitude of ECG ST-segment elevation during coronary balloon occlusion (Figure 3).6,7 IS, measured as the degree of ECG ST-segment elevation during a 1-minute coronary occlusion, is influenced by the following factors: duration of occlusion, ischemic area at risk for myocardial infarction (AR), collateral blood supply to the ischemic zone, ischemic preconditioning, and myocardial oxygen consumption.8 In the context of a single brief artificial coronary occlusion of uniform duration without preceding bouts of ischemia (Figure 3),6 ECG signs of ischemia are influenced predominantly by the AR and by collateral supply to this region. Furthermore, Figure 1B3 illustrates that AR and collateral supply are inversely related to each other (ie, AR tends to shrink toward zero in the presence of well-functioning collaterals). They are termed sufficient if they prevent an ECG ST-segment elevation of ≥0.1 mV during a 1-minute coronary balloon occlusion; otherwise, they are termed insufficient collaterals. Figure 1. Schematic drawing of the coronary artery circulation without (A) and with interarterial anastomoses (B) between the right coronary artery and the occluded left anterior descending artery (occluded downstream …

Abstract 2651: Ischemic Cascade: Sequence of ECG, Acoustic Cardiographic Changes, and Angina during Coronary Occlusion

Background: Previous studies suggest that ventricular function may be impaired without or prior to ECG changes during ischemia. Using diastolic third and fourth heart sounds (S3 and S4), a non-invasive measurement of ventricular function, our study investigated whether diastolic heart sounds occur earlier than electrical changes or angina during ischemia. Methods: To determine the sequence of ECG, diastolic heart sounds, and anginal ischemic symptoms, a prospective observational study was performed in 21 subjects undergoing cardiac catheterization and percutaneous coronary intervention (PCI). Subjects had both ST-segment amplitude changes &gt;2 standard deviations above the baseline during PCI-related coronary occlusion, as well as new or increased intensity S3 or S4 measured by computerized acoustic cardiography. The sequence of resolution of these noninvasive signs of ischemia was also examined following balloon deflation. Results: Electrocardiographic ST amplitude changes were the earliest sign of ischemia (mean onset, 21 seconds), and they were also the first to resolve after balloon deflation. New or increased intensity diastolic heart sounds followed ECG changes (mean onset S4, 24.7 seconds; S3, 38.1 seconds: Tables 1 &amp; 2 ). Anginal symptoms occurred in only 2 of the 21 subjects during ischemia with a mean onset time of 67.5 seconds. Conclusion: ECG signs of ischemia precede functional changes as measured by new or intensified S3 and/or S4. Angina rarely occurs during PCI-induced ischemia, but if present, is the last event in the ischemic cascade. Table 1. Sequence of noninvasive signs of ischemia during coronary occlusion (n=21) Table 2. Resolution of noninvasive signs of ischemia after balloon deflation (n=18)

Reciprocal relationship between left ventricular filling pressure and the recruitable human coronary collateral circulation

The aim of our study in patients with coronary artery disease (CAD) and present, or absent, myocardial ischaemia during coronary occlusion was to test whether (i) left ventricular (LV) filling pressure is influenced by the collateral circulation and, on the other hand, that (ii) its resistance to flow is directly associated with LV filling pressure. In 50 patients with CAD, the following parameters were obtained before and during a 60 s balloon occlusion: LV, aortic (Pao) and coronary pressure (Poccl), flow velocity (Voccl), central venous pressure (CVP), and coronary flow velocity after coronary angioplasty (V(Ø-occl)). The following variables were determined and analysed at 10 s intervals during occlusion, and at 60 s of occlusion: LV end-diastolic pressure (LVEDP), velocity-derived (CFIv) and pressure-derived collateral flow index (CFIp), coronary collateral (Rcoll), and peripheral resistance index to flow (Rperiph). Patients with ECG signs of ischaemia during coronary occlusion (insufficient collaterals, n = 33) had higher values of LVEDP over the entire course of occlusion than those without ECG signs of ischaemia during occlusion (sufficient collaterals, n = 17). Despite no ischaemia in the latter, there was an increase in LVEDP from 20 to 60 s of occlusion. In patients with insufficient collaterals, CFIv decreased and CFIp increased during occlusion. Beyond an occlusive LVEDP > 27 mmHg, Rcoll and Rperiph increased as a function of LVEDP. Recruitable collaterals are reciprocally tied to LV filling pressure during occlusion. If poorly developed, they affect it via myocardial ischaemia; if well grown, LV filling pressure still increases gradually during occlusion despite the absence of ischaemia indicating transmission of collateral perfusion pressure to the LV. With low, but not high, collateral flow, resistance to collateral as well as coronary peripheral flow is related to LV filling pressure in the high range.

Risk Assessment in Patients with Ruptured Abdominal Aortic Aneurysms

Objectives: Surgery of ruptured abdominal aortic aneurysms is associated with a high mortality rate, mostly related to multi-organ-failure after a prolonged intensive care therapy. In a retrospective study attempts are made to identify individual organ-dysfunction risk profiles influencing the outcome.Methods: Fifty seven patients (53 men, 4 women, mean age 71.8 ±8.8 years) with ruptured abdominal aortic aneurysms underwent graft replacement in a three year period. Fourty eight preoperative, 13 intraoperative and 34 postoperative variables were analyzed. A multi-organ dysfunction (MOD) score was used.Results: The perioperative mortality rate was 31%. Significance of pre-existing risk factors at admission was identified only for cardiovascular diseases. Multiple linear regression analysis indicated that hemoglobin < 90g/l, systolic blood pressure < 80 mmHg and ECG signs of ischemia at admission are highly significant risk factors. Patients, who died later than 48 hours postoperatively, deceased mainly from MOD (93%) and required intensive care significantly longer than surviving patients (p < 0.0005). All patients with a MOD score > 4 died (n = 7). These patients required 26% of all ICU-days and 72% of the ICU-days of the nonsurvivors.Conclusion: Patients with ruptured aortic aneurysms should not be excluded from treatment. However, a physiological scoring system after 48 h appears justifiable in order to decide on the appropriateness of continued ICU support.

Treatment of Ruptured Abdominal Aortic Aneurysm, a Permanent Challenge or a Waste of Resources? Prediction of Outcome Using a Multi-organ-dysfunction Score

Objectives: in a retrospective study, attempts have been made to identify individual organ-dysfunction risk profiles influencing the outcome after surgery for ruptured abdominal aortic aneurysms. Methods: out of 235 patients undergoing graft replacement for abdominal aortic aneurysms, 57 (53 men, four women, mean age 72 years [s.d. 8.8]) were treated for ruptured aneurysms in a 3-year period. Forty-eight preoperative, 13 intraoperative and 34 postoperative variables were evaluated statistically. A simple multi-organ dysfunction (MOD) score was adopted.Results: the perioperative mortality was 32%. Three patients died intraoperatively, four within 48 h and 11 died later. A significant influence for pre-existing risk factors was identified only for cardiovascular diseases. Multiple linear-regression analysis indicated that a haemoglobin <90 g/l, systolic blood pressure <80 mmHg and ECG signs of ischaemia at admission were highly significant risk factors. The cause of death for patients, who died more than 48 h postoperatively, was mainly MOD. All patients with a MOD score ≥4 died (n=7). These patients required 27% of the intensive-care unit (ICU) days of all patients and 72% of the ICU days of the non-survivors. Conclusion: patients with ruptured aortic aneurysms from treatment should not be excluded. However, a physiological scoring system after 48 h appears justifiable in order to decide on the appropriateness of continual ICU support.

Signos predictores de enfermedad coronaria multivaso en la ecocardiografía con dobutamina

To assess the ability of dobutamine echocardiography to detect multivessel coronary artery disease and to determine predictive factors for multivessel disease with or without beta-blockers. A total of 101 patients underwent dobutamine stress echocardiography and coronary angiography (evaluation of chest pain 76, extent of coronary disease after myocardial infarction 19, other indications 6). Ten patients in whom the test was prematurely terminated were excluded. Out of 91 patients who underwent dobutamine echocardiography, 54 patients had multivessel disease (sensitivity of dobutamine test 93%, specificity 46%). Heart rate at the maximum dose of dobutamine or atropine was 88 +/- 21 beats/min for multivessel diseases and 104 +/- 21 beats/min without multivessel disease (p < 0.001). A cut-off value < 94 beats/min discriminated patients at risk for multivessel disease. After adjusting for treatment with beta-blockers, heart rate < 94 beats/min, ECG signs of ischemia, and abnormalities on baseline echocardiogram with remote asynergies during dobutamine testing were independent predictors of multivessel disease in the multivariate analysis (probability > 90% when at least two factors were present). A heart rate < 94 beats/min at peak dose of dobutamine or after atropine, ECG signs of ischemia, and the presence of abnormalities on echocardiogram at rest with remote asynergies during dobutamine stress testing were independent predictive factors of multivessel coronary artery disease.

Hypertension in Diabetes Study (HDS): I. Prevalence of hypertension in newly presenting type 2 diabetic patients and the association with risk factors for cardiovascular and diabetic complications.

To determine the prevalence of hypertension in newly diagnosed type 2 diabetic patients and its association with risk factors for cardiovascular and diabetic complications. Cross-sectional study. Newly diagnosed type 2 diabetic patients (n = 3648, mean age 52 years, 59% male) recruited for the UK Prospective Diabetes Study (UKPDS). Blood pressure, body mass index, waist:hip ratio, ECG signs of ischaemia and of left ventricular hypertrophy (Minnesota code), fasting plasma glucose, urate, creatinine, insulin, triglycerides, high-density lipoprotein-, low-density lipoprotein- and total cholesterol, urinary albumin:creatinine ratio, retinopathy grading. Thirty-nine per cent of the patients (35% of the males, 46% of the females) were hypertensive (mean blood pressure > or = 160 systolic and/or > or = 90 mmHg diastolic 2 and 9 months after diagnosis of diabetes, or taking antihypertensive therapy). The hypertensive patients had a greater mean body mass index (30.1 versus 28.0 kg/m2, P < 0.0001) than the normotensive patients. They also had higher fasting plasma triglyceride (1.94 versus 1.69 mmol/l, P < 0.0001) and insulin (15.0 versus 12.8 mU/l, P < 0.0001) levels but these associations disappeared or weakened when obesity was taken into account. Hypertensive compared with normotensive subjects suffered a higher prevalence of cardiovascular events before the diagnosis of diabetes (4.8 versus 2.5%, P < 0.0001), of microalbuminuria (albumin:creatinine ratio > 5.0 g/mol; 24 versus 14%, P < 0.0001), of ECG signs of probable and possible ischaemia (24 versus 14%, P < 0.0001) and of left ventricular hypertrophy (8.5 versus 3.8%; P < 0.0001). The prevalence of retinopathy was similar in the two groups. Hypertension is common in newly diagnosed type 2 diabetes and is associated with obesity. The association between hypertension and higher triglyceride and insulin levels may be secondary to obesity in this population. An association between hypertension and cardiovascular complications is already apparent at diagnosis of diabetes.

Myocardial ischaemia as judged from transoesophageal echocardiography and ECG in the early phase after coronary artery bypass surgery

The incidence of myocardial ischaemia, as diagnosed by transoesophageal echocardiography (TEE) versus ECG, and the relationship between ischaemic events and haemodynamic parameters were studied in 30 patients in the early phase after coronary artery bypass grafting. Information comprising invasive haemodynamics, TEE measurements, and 12-lead ECG was obtained on arrival of the patient in the intensive care unit (ICU), and then hourly in the ICU for 5 h. In the ICU, TEE signs of ischaemia were found in 14 patients and ECG signs of ischaemia in six patients. The ischaemic events were not related to levels of blood pressure or heart rate. Three patients showed signs of myocardial infarction postoperatively. All three of these patients showed both TEE and ECG signs of ischaemia in the ICU. It was concluded that TEE reveals more ischaemic events than ECG in the early postoperative period and that these ischaemic events do not correlate with the haemodynamic indices.

Epidemiological study of the cardiovascular effects of carbon disulphide.

In an extensive health survey 115 male viscose rayon workers exposed to carbon disulphide (CS2) and 76 referents not exposed to this chemical were interviewed using the WHO cardiovascular questionnaire and responded to a self-administered questionnaire. A 12-lead ECG was taken and coded using the Minnesota code. Blood pressure (BP) was measured electronically and blood was examined for lipoproteins. In the viscose rayon factory the working conditions had not changed since 1932. Personal monitoring performed in 17 jobs, showed exposures varying from 4 to 112 mg/m3. For each individual a CS2 cumulative exposure index (CS2 index) was calculated. There were no significant differences between exposed and referents concerning the prevalence of angina, history of myocardial infarction, intermittent claudication and ECG signs of ischaemia. Blood pressure, low density lipoprotein (LDL)-cholesterol and the apolipoproteins A1 and B rose while high density lipoprotein (HDL)-cholesterol, the HDL-cholesterol/apolipoprotein A1 and the LDL-cholesterol/apolipoprotein B ratios decreased significantly with increasing exposure. Adjustment for age, body mass index, smoking, alcohol consumption, stress and tension at work, shift work, noise exposure and educational level in multiple linear regression analysis showed significant effects of the CS2 index on systolic BP, diastolic BP, cholesterol, HDL-cholesterol, LDL-cholesterol, apolipoprotein A1, apolipoprotein B, the LDL cholesterol/apolipoprotein B and HDL cholesterol/apolipoprotein A1 ratios; there were no significant effects on the triglycerides.

Felodipine in chronic stable angina: a randomized, double-blind, placebo-controlled, crossover study

To investigate the antianginal efficacy and tolerability of felodipine, a new dihydropyridine calcium antagonist, 20 patients with stable exertional angina, not completely controlled by beta-blocker monotherapy, entered a randomized, double-blind, placebo-controlled, crossover study. Patients on standard beta-blocker therapy, who had at least 3 weekly anginal episodes and a reproducible exercise test (stopped for angina and ECG signs of ischaemia) at the end of 2 weeks placebo treatment, were eligible for the study. They were randomized to one sequence of treatment: felodipine 5 mg twice daily for 2 weeks followed by placebo for a further 2 weeks, or vice versa. Beta-blocker treatment was unchanged throughout the study. A treadmill test was carried out at the end of each crossover period, 2-4 h after drug administration. The number of anginal attacks and nitroglycerin consumption was recorded on a diary card. At rest, felodipine significantly (P less than 0.05) reduced standing systolic but not diastolic blood pressure. Heart rate was not modified by the active treatment. At ischaemic threshold and at peak exercise, heart rate, systolic blood pressure and rate-pressure product remained unchanged. Exercise duration was increased by felodipine (P less than 0.01) and maximal ST change was reduced (P less than 0.01). Time to 1 mm ST depression was prolonged non-significantly by felodipine (basal 5.7 +/- 1.5, felodipine 7.4 +/- 2.0, placebo 6.6 +/- 1.5 min). The number of patients who stopped exercise due to angina and ST change was 20/20 at baseline, 16/20 with placebo and 10/20 with felodipine. Felodipine significantly reduced weekly anginal episodes (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Impaired relationship between Doppler echocardiographic parameters of diastolic function and left ventricular filling pressure during acute ischemia

The relationship between left ventricular filling pressure and Doppler echocardiographic parameters of diastolic mitral flow (MF) was evaluated in patients with ischemic heart disease during acute ischemia induced by percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending artery. Thirty-two patients were examined by simultaneous recordings of the Doppler MF signal and the mean pulmonary capillary wedge pressure (PCm) as an approximation of left ventricular filling pressure. At rest PCm was correlated with the early/late velocity integral ratio (Ei/Ai: r = 0.62: p < 0.0001 n = 32). In 25 of 32 patients the recordings during PTCA could be evaluated. At the end of the inflation (duration: 69 ± 24 seconds) PCm increased from 11.2 ± 5.5 to 17.2 ± 7.2 mm Hg ( p < 0.001), and total MF integral as an index of systolic ventricular function decreased by 14.9 ± 12.8% ( p < 0.001). Inasmuch as both early and late velocity integrals were reduced during PTCA, the Ei/Ai ratio did not change significantly (1.41 ± 0.51 to 1.34 ± 0.60; NS). In a subgroup of inflations without ECG signs of ischemia, Ei was decreased without a concomitant decrease in Ai, thus leading to a decrease in the Ei/Ai ratio (1.36 ± 0.43 to 1.17 ± 0.31; p < 0.05). Summarizing the events during PTCA, a steady increase in PCm was observed, whereas the Ei/Ai ratio was slightly decreased. Thus the observation at rest that an elevated PCm was associated with an elevated Ei/Ai was no longer valid during PTCA (Ei/Ai : r = 0.28; NS). A significant correlation was found between parameters of Doppler MF and PCm in patients with ischemic heart disease at rest. During PTCA this relationship was attenuated. Therefore noninvasive assessment of left ventricular filling pressures during acute ischemia by Doppler echocardiography does not seem feasible.

Cardiovascular reactions and respiratory events during platelet activating factor-induced shock

The platelet activating factor (PAF), a low molecular phospholipid, plays an important role in inflammation, anaphylaxis, and shock state development. In the isolated perfused guinea pig heart, PAF induces a decrease in coronary flow and cardiac contractility and atrioventricular conduction disturbances. Furthermore, PAF mediates a powerful bronchoconstrictory action causing a severe impairment in respiratory function. In the present study an attempt was made to separate cardiac from respiratory events during PAF-induced shock in vivo. PAF was injected intravenously (0.1-10 micrograms/kg) into anesthetized guinea pigs ventilated with room air or 100% oxygen. Administration of 10 micrograms/kg PAF was uniformly lethal: already within 2 min, cardiac output decreased by 60% and end-diastolic left ventricular pressure increased markedly indicating cardiac failure. ECG recordings showed signs of acute myocardial ischemia. Arrhythmias occurred in terms of atrioventricular conduction delay. Blood pressure initially increased, then declined continuously to below baseline within 10 min. All animals died within 25 min. Ventilation with room air was paralleled by development of severe hypoxia. However, under ventilation with 100% oxygen a dissociation between PAF-mediated cardiac and respiratory effects occurred. It is concluded that the PAF-induced shock is primarily based on direct cardiac damage. Furthermore, the ECG signs of ischemia are most likely due to coronary spasms.

Incidence of Arrhythmias and Myocardial Ischaemia During Haemodialysis and Haemofiltration

Thirty-two patients (10 male, 22 female; age 37-82 years) undergoing maintenance haemodialysis or haemofiltration were studied by means of Holter device capable of simultaneously analysing rhythm and ST-changes in three leads. Twenty-five patients were on haemodialysis, seven on haemofiltration, mean duration of haemodialysis/haemofiltration being 3.4 +/- 3 years. Incidence of ventricular tachycardia was low, being detected only in 1 of 32 patients. Ventricular premature beats in excess of 10/h during a period of 2 h were found in 8 of 32 patients and 100 supraventricular premature beats for 2 h or more in 4 of 32 patients. Both ventricular premature beats and supraventricular premature beats were most frequently recorded during the last hour of haemodialysis/haemofiltration. ECG signs of ischaemia were detected in eight patients, four of whom were asymptomatic. Ischaemia also occurred predominantly during the last hour of haemodialysis/haemofiltration. Two symptomatic patients displayed neither arrhythmias nor ST-changes while being monitored. The study shows that silent ischaemia and arrhythmias in patients undergoing chronic haemodialysis/haemofiltration may not be infrequent. Recognition of these events could be of importance in the management of these patients.