ABSTRACT
A precise diagnosis of diastolic dysfunction is often difficult and requires invasive techniques to determine left ventricular volume, relaxation, and compliance properties. At this current point of time there is no single non-invasive index available to adequately reflect diastolic function, perhaps because of the numerous factors that can alter diastolic function. In most clinical settings, diastolic function is estimated using Doppler echocardiography. Cardiac magnetic resonance imaging (CMRI) is yet another emerging modality for diastolic function analysis. Here we present a comprehensive review of the various parameters used to assess diastolic function as part of diagnosis of clinical syndrome "Heart failure with preserved ejection fraction (HFPEF)".
ABSTRACT
INTRODUCTION: The best strategy in patients with prior coronary artery bypass graft surgery (CABG) who present with non-ST elevation myocardial infarction (NSTEMI) remains less well defined. We compare the characteristics, therapeutic interventions and outcomes of patients with prior CABG presenting with NSTEMI. METHODS: All patients who presented to our hospital during 2007-2012 with available electronic records were analysed retrospectively. Outcomes were compared between patients who underwent coronary angiography or percutaneous coronary intervention (PCI) versus those who were treated medically. RESULTS: A total of 117 patients were analysed. Of that, 79 patients were managed medically while 38 underwent early angiography, of which only 11 (9.5%) received PCI. Patients treated medically (did not undergo angiography) were older (74±10 vs70±8; p=0.05). ECG changes were the only independent predictor for early angiography (OR 0.4, 95% CI 0.15 to 0.99; p=0.05) while recurrent chest pain (OR 0.2, 95% CI 0.05 to 0.97; p=0.05) predicted PCI on multivariate analysis. The PCI group had higher Global Registry of Acute Cardiac Events (GRACE) score (176±29 vs 150±31; p=0.01). No significant difference was found in readmission rates, morbidity (unstable angina pectoris, NSTEMI, ST elevation myocardial infarction (STEMI), or combination) or mortality at 12â months between the groups who underwent angiography, PCI, or treated medically on univariate and multivariate analysis. CONCLUSIONS: The opportunity to intervene in prior CABG patients presenting with NSTEMI is often low. Initial medical management may be a reasonable option in carefully selected patients particularly in the absence of ongoing symptoms, ECG changes or very high GRACE scores. Further studies are required to evaluate the safety of non-invasive strategies in managing this population.
ABSTRACT
BACKGROUND: The incidence of perioperative myocardial infarction (PMI) globally is known to be around 2 to 3% and can prolong hospitalization, increased morbidity and mortality. Little is known about the pathophysiology and risk factors for PMI. We investigate the presence of elevated novel cardiac markers and preoperative coronary artery plaque through contemporary laboratory techniques to determine the correlation with PMI, as well as studying ivabradine and atorvastatin as protective pharmacotherapies against PMI in the context of orthopedic surgery. METHODS/DESIGN: We aim to enroll 200 patients aged above 60 years who suffer from neck of femur fracture requiring surgery. Patients will be randomized to four arms (no study drugs, atorvastatin only, ivabradine only and ivabradine and atorvastatin). Our primary outcome is incidence of PMI. All patients will receive an electrocardiogram, cardiac echocardiography, measurement of novel cardiac biomarkers and computed tomography (CT) coronary angiography. A telephone interview post discharge will be conducted at 30 days, 60 days and 1 year. DISCUSSION: We postulate that ivabradine and atorvastatin will reduce the rate and magnitude of PMI following surgery by reducing heart rate and attenuating catecholamine-induced tachycardia postoperatively. Secondly, we postulate that postoperative reduction in heart rate and catecholamine-induced tachycardia with ivabradine will correlate with a reduction in cardiovascular novel biomarkers which will reduce atrial stretch and postoperative incidence of arrhythmia. We aim to demonstrate that treatment with ivabradine and atorvastatin will cause a reduction in the incidence and magnitude of PMI, the benefit of which is derived primarily in patients with greater atherosclerotic burden as measured by higher CT coronary calcium scores. TRIAL REGISTRATION: This study protocol has been listed in the Australia New Zealand Clinical Trial Registry (registration number: ACTRN12612000340831) on 23 March 2012.
