Objective To review the clinical characteristics and current management strategy and to examine the factors to be considered in the selection of treatment options for mitral regurgitation (MR) in elderly inpatients.Methods Elderly patients(≥60years old)who had been diagnosed with moderate to severe MR by transthoracic echocardiography and hospitalized from May 1,2014 to April 30,2015were included in this study (N=680).Patients were grouped according to therapy:the surgery group (n=372) and the medication group (n=308).Data at baseline including medical history and echocardiography were collected for comparison between the two groups and for analysis of factors associated with treatment choice.Results Of the 680 patients with moderate to severe MR,45.3％ were treated with medication.Compared with the surgery group,patients in the medication group were older,with a lower prevalence of primary MR,a higher prevalence of coronary heart disease and higher Euroscore-Ⅱ scores (all P＜0.01).Furthermore,the medication group had a lower prevalence of moderate MR(75/308 or 24.4％ vs.200/372 or 53.8％,P＜ 0.01),a lower left ventricular ejection fraction (47.8 ± 16.1) ％ vs (61.5 ± 9.2)％(P＜0.01),and a larger left ventricular end diastolic diameter(59.2±11.4)mmw (55.8±8.8)mm (P＜ 0.01).Besides,multivariable analysis revealed that regurgitation grade,left ventricular ejection fraction,multiple valve disease,age,and diabetes were correlated with therapy decisions(OR=62.067,1.089,4.791,0.879 and 0.414,respectively,P＜0.01 or P＜0.05).Conclusions Old age,impaired left ventricular ejection fraction,low regurgitation grade,diabetes,and absence of multiple valves are the most salientfactors for which surgery should not be selected.

Mitochondria plays a key role in providing ATP for the energy-consuming cardiac tissues. Mitochondrial cardiomyopathy is a myocardial condition characterized by abnormal heart structure and/or function secondary to genetic defects involving the mitochondrial respiratory chain. The typical cardiac manifestations of mitochondrial cardiomyopathy include hypertrophic and dilated cardiomyopathy,while left ventricular myocardial noncompaction is less common. Recent research has suggested that most mitochondrial diseases result from mitochondrial DNA mutation,which can be found in genes that encode ancillary proteins needed for genetic transcription (tRNA),in genes that encode subunits of the electron transport chain complexes,or in genes that control the activities of the mitochondria called D-loop zone. However,the exact physiological mechanisms remain unclear. This review summarizes the recent advances in the molecular mechanism of mitochondrial cardiomyopathy.

Mitochondrial cardiomyopathy (MCM) is a series of myocardial conditions characterized by abnormal heart-muscle structure,function,or both,secondary to genetic defects involving the mitochondrial respiratory chain,in the absence of concomitant coronary artery disease,hypertension,valvular disease,or congenital heart disease. MCM patients typically have hypertrophic or dilated cardiomyopathy. Arrhythmias and left ventricular myocardial noncompaction are less common,and heart failure may occur as the first symptom in some patients. Since MCM patients often have symptoms of multiple organ involvement,the symptoms are not specific and the diagnosis can be difficult. Thus,awareness of this disease must be increased in clinical settings. Treatments for MCM are mostly supportive and nonspecific. In this review,we summarize new advances in the diagnosis and management of MCM,with an improve the clinical management of this disease.