Diagnosis and treatment of heart failure with preserved left ventricular ejection fraction

Nearly six million people in United States have heart failure.Fifty percent of these people have normal left ventricular(LV)systolic heart function but abnormal diastolic function due to increased LV myocardial stiffness.Most commonly,these patients are elderly women with hypertension,ischemic heart disease,atrial fibrillation,obesity,diabetes mellitus,renal disease,or obstructive lung disease.The annual mortality rate of these patients is 8%-12%per year.The diagnosis is based on the history,physical examination,laboratory data,echocardiography,and,when necessary,by cardiac catheterization.Patients with obesity,hypertension,atrial fibrillation,and volume overload require weight reduction,an exercise program,aggressive control of blood pressure and heart rate,and diuretics.Miniature devices inserted into patients for pulmonary artery pressure monitoring provide early warning of increased pulmonary pressure and congestion.If significant coronary heart disease is present,coronary revascularization should be considered.

Recent advances in the diagnosis and treatment of acute myocardial infarction

The Third Universal Definition of Myocardial Infarction(MI) requires cardiac myocyte necrosis with an increase and/or a decrease in a patient's plasma of cardiac troponin(cT n) with at least one cT n measurement greater than the 99 th percentile of the upper normal reference limit during:(1) symptoms of myocardialischemia;(2) new significant electrocardiogram(ECG) ST-segment/T-wave changes or left bundle branch block;(3) the development of pathological ECG Q waves;(4) new loss of viable myocardium or regional wall motion abnormality identified by an imaging procedure; or(5) identification of intracoronary thrombus by angiography or autopsy.Myocardial infarction,when diagnosed,is now classified into five types.Detection of a rise and a fall of troponin are essential to the diagnosis of acute MI.However,high sensitivity troponin assays can increase the sensitivity but decrease the specificity of MI diagnosis.The ECG remains a cornerstone in the diagnosis of MI and should be frequently repeated,especially if the initial ECG is not diagnostic of MI.There have been significant advances in adjunctive pharmacotherapy,procedural techniques and stent technology in the treatment of patients with MIs.The routine use of antiplatelet agents such as clopidogrel,prasugrel or ticagrelor,in addition to aspirin,reduces patient morbidity and mortality.Percutaneous coronary intervention(PCI) in a timely manner is the primary treatment of patients with acute ST segment elevation MI.Drug eluting coronary stents are safe and beneficial with primary coronary intervention.Treatment with direct thrombin inhibitors during PCI is non-inferior to unfractionated heparin and glycoprotein Ⅱb/Ⅲa receptor antagonists and is associated with a significant reduction in bleeding.The intra-coronary use of a glycoprotein Ⅱb/Ⅲa antagonist can reduce infarct size.Pre- and post-conditioning techniques can provide additional cardioprotection.However,the incidence and mortality due to MI continues to be high despite all these recent advances.The initial ten year experience with autologous human bone marrow mononuclear cells(BMCs) in patients with MI showed modest but significant increases in left ventricular(LV) ejection fraction,decreases in LV endsystolic volume and reductions in MI size.These studies established that the intramyocardial or intracoronary administration of stem cells is safe.However,many of these studies consisted of small numbers of patients who were not randomized to BMCs or placebo.The recent LateT ime,Time,and Swiss Multicenter Trials in patientswith MI did not demonstrate significant improvement in patient LV ejection fraction with BMCs in comparison with placebo.Possible explanations include the early use of PCI in these patients,heterogeneous BMC populations which died prematurely from patients with chronic ischemic disease,red blood cell contamination which decreases BMC renewal,and heparin which decreases BMC migration.In contrast,cardiac stem cells from the right atrial appendage and ventricular septum and apex in the SCIPIO and CADUCEUS Trials appear to reduce patient MI size and increase viable myocardium.Additional clinical studies with cardiac stem cells are in progress.