Prognostic value of cardiovascular magnetic resonance in patients with suspected arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: Early recognition and accurate risk stratification are important in the management of arrhythmogenic right ventricular cardiomyopathy (ARVC). Identification of predictors of outcome by cardiovascular magnetic resonance (CMR) in patients undergoing evaluation for ARVC is limited. We investigated the predictive value of morphological abnormalities detected by CMR for major clinical events in patients with suspected ARVC. METHODS: We performed a longitudinal study on 369 consecutive patients with at least one criterion for ARVC. Abnormal CMR was defined by the presence of one of the following: increased right ventricular (RV) volumes, reduced RV ejection fraction, RV regional wall motion abnormalities, myocardial fatty infiltration, and myocardial fibrosis. The end-point was a composite of cardiac death, sustained ventricular tachycardia, ventricular fibrillation, and appropriate ICD discharge. RESULTS: Twenty patients met the composite end-point over a mean follow-up of 4.3±1.5 years. An abnormal CMR was an independent predictor of outcomes (p<0.001). The presence of multiple abnormalities heralded a particular high risk of events (HR 23.0, 95% CI 5.7-93.2, p<0.001 for 2 abnormalities; HR 35.8, 95% CI 9.7-132.6, p<0.001 for 3 or more abnormalities). The positive predictive value of an abnormal CMR study was 21.0% for an adverse event, whilst the negative predictive value of a normal CMR study was 98.8% over the follow-up period. CONCLUSIONS: CMR provides important prognostic information in patients under evaluation for ARVC. A normal study portends a good prognosis. Conversely, the presence of multiple abnormalities identifies a high risk group of patients who may benefit from ICD implantation.

Role of multidetector computed tomography in the diagnosis and management of patients attending the rapid access chest pain clinic, The Scottish computed tomography of the heart (SCOT-HEART) trial: study protocol for randomized controlled trial.

BACKGROUND: Rapid access chest pain clinics have facilitated the early diagnosis and treatment of patients with coronary heart disease and angina. Despite this important service provision, coronary heart disease continues to be under-diagnosed and many patients are left untreated and at risk. Recent advances in imaging technology have now led to the widespread use of noninvasive computed tomography, which can be used to measure coronary artery calcium scores and perform coronary angiography in one examination. However, this technology has not been robustly evaluated in its application to the clinic. METHODS/DESIGN: The SCOT-HEART study is an open parallel group prospective multicentre randomized controlled trial of 4,138 patients attending the rapid access chest pain clinic for evaluation of suspected cardiac chest pain. Following clinical consultation, participants will be approached and randomized 1:1 to receive standard care or standard care plus ≥64-multidetector computed tomography coronary angiography and coronary calcium score. Randomization will be conducted using a web-based system to ensure allocation concealment and will incorporate minimization. The primary endpoint of the study will be the proportion of patients diagnosed with angina pectoris secondary to coronary heart disease at 6 weeks. Secondary endpoints will include the assessment of subsequent symptoms, diagnosis, investigation and treatment. In addition, long-term health outcomes, safety endpoints, such as radiation dose, and health economic endpoints will be assessed. Assuming a clinic rate of 27.0% for the diagnosis of angina pectoris due to coronary heart disease, we will need to recruit 2,069 patients per group to detect an absolute increase of 4.0% in the rate of diagnosis at 80% power and a two-sided P value of 0.05. The SCOT-HEART study is currently recruiting participants and expects to report in 2014. DISCUSSION: This is the first study to look at the implementation of computed tomography in the patient care pathway that is outcome focused. This study will have major implications for the management of patients with cardiovascular disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01149590.

B-type natriuretic Peptide is associated with both augmentation index and left ventricular mass in diabetic patients without heart failure.

BACKGROUND: B-type natriuretic peptide (BNP) increases the risk of death and cardiovascular events in patients without heart failure, even at BNP values within the "normal" range. The reasons for this are unclear. METHODS: We performed two separate studies (n = 33 and n = 129) on subjects with type 2 diabetes mellitus in whom frank left ventricular systolic dysfunction had been excluded to ascertain whether a high-normal BNP could be identifying either greater augmentation of the ascending aortic pressure wave, increased left ventricular mass, or a subtly lower left ventricular ejection fraction (but within the normal range). RESULTS: Our results demonstrate that an increased augmentation index is an independent predictor of BNP levels even when BNP levels are within the normal range (P = .006 in study one and P = .007 in study two). A high-normal BNP also correlated with increased left ventricular mass and (P = .021) with a subtly lower left ventricular ejection fraction (P < .001). CONCLUSIONS: We found that high-normal BNP levels identified increased augmentation of the ascending aortic pressure wave as well as subtle left ventricular abnormalities.

B-type natriuretic peptide as an alternative way of assessing total cardiovascular risk in patients with diabetes mellitus.

Cardiovascular risk scores are available but are often not calculated in busy clinics for numerous practical reasons. B-type natriuretic peptide (BNP) may be an alternative way of identifying subjects who have a high total cardiovascular risk score. We compared BNP level with Framingham 10-year Risk Scores for coronary heart disease and stroke and New Zealand Cardiovascular Risk Scores in 231 patients who had type 2 diabetes and no preexisting coronary heart disease or stroke. There was a significant correlation between log BNP and 10-year risk for coronary heart disease and stroke, and there were significantly higher BNP levels in those who had high cardiovascular risk as assessed by the New Zealand Risk Score. BNP may be a useful way of measuring total cardiovascular risk, thus having the potential to better target the most aggressive primary preventive therapies toward the most needy.

How much echo left ventricular hypertrophy would be missed in diabetics by applying the Losartan Intervention For Endpoint Reduction electrocardiogram criteria to select patients for angiotensin receptor blockade?

OBJECTIVE: The Losartan Intervention For Endpoint Reduction (LIFE) study demonstrated a clear mortality benefit in treating hypertensive patients with electrocardiogram (ECG) evidence of left ventricular hypertrophy (LVH) with losartan rather than atenolol. Previous studies have also shown that identifying and treating echo LVH is associated with prognostic benefits in hypertensive subjects, and is independent of the presence of ECG LVH. We sought to determine how many cases of echo LVH would be missed by applying the ECG criteria for LVH used in the LIFE study. DESIGN: A prospective study of 219 patients with type 2 diabetes recruited from the hospital diabetic clinic. METHODS: Fifteen ECG criteria were assessed on each subject and compared with the presence or absence of LVH on echocardiography. RESULTS: All the proposed ECG criteria are poor at identifying echo LVH in people with diabetes. CONCLUSION: Using ECG LVH to select patients for angiotensin receptor blockade would lead to many diabetics with echo LVH missing out on the benefits of treatment. This assumes that the benefits seen in the LIFE study would also occur if the LIFE strategy were extended to echo LVH patients as well as to ECG LVH patients.

The role of aldosterone in heart failure and the clinical benefits of aldosterone blockade.

Aldosterone has a variety of detrimental effects on the heart and vasculature and is increasingly recognized as an important target in chronic heart failure, as illustrated by the Randomized Aldactone Evaluation Study. In this article, the evidence supporting the cardiovascular effects of aldosterone in humans and the proven benefits of aldosterone-receptor antagonists in heart failure shall be discussed.

Screening for treatable left ventricular abnormalities in diabetic patients.

Cardiovascular disease is the leading cause of death in patients with diabetes mellitus. Attempts to improve this statistic tend to focus primarily on the prevention of coronary artery disease. However, coronary artery disease is not the sole cause of cardiac death in diabetic patients; left ventricular dysfunction (LVD) and left ventricular hypertrophy (LVH) are also implicated and, unlike coronary artery disease, are ideal targets for screening. The treatment of left ventricular abnormalities, even when these are asymptomatic, is associated with prognostic benefit. Prescreening diabetic patients with plasma B-type natriuretic peptide (BNP) may permit identification of those who are likely to have left ventricular abnormalities, so that they may be put forward for echocardiography and receive targeted therapy.

Vasopeptidase inhibitors in heart failure.

Considerable attention has recently focused on the vasopeptidase inhibitors (VPI), a new class of drug that combines angiotensin-converting enzyme (ACE) inhibitor activity with inhibition of natriuretic peptide breakdown. In theory, a drug with these properties may be beneficial both in hypertension and in heart failure. Whilst the efficacy of VPIs in hypertension has been consistently demonstrated in pre-clinical and clinical studies, the role of VPIs, if any, in heart failure is less clear, since numerous small studies have produced conflicting results. Furthermore, preliminary results from the recently completed Omapatrilat Versus Enalapril Randomised Trial of Utility in Reducing Events (OVERTURE) study have failed to establish the VPI, omapatrilat, as a first line therapy in the treatment of chronic heart failure. We review the literature on VPIs in heart failure and discuss possible reasons for the reported lack of benefit over ACE inhibitors.