Analysis Of Prognostic Factors Of Noncompaction Of Ventricular Myocardium

BackgroundNoncompaction of Ventricular Myocardium(NVM)is a relatively rare cardiomyopathy.The trabeculation and deep intertrabecular recesses which communicate with the left ventricular cavity are the characteristic.It is also described as isolated noncompaction of ventricular myocardium,INVC in clinic for the reason that it exists with no other complications sometimes.The clinical manifestation of the patients with NVM is diversiform such as left ventricular systolic dysfunction,arrhythmia and thromboembolism.Left ventricular systolic dysfunction and dyspnea are the most common clinlcal symptoms among them.ObjectiveTo study the clinical and imaging information of 36 patients retrospectively and analyze the prognosis of the patients and the prognosis factors preliminary.Methods36 patients with NVM were collected from January 2012 to December 2015 and the clinical date and outcomes were reviewed retrospectively.We measured the thickness of compacted layer(C)and the ratio of thick noncompacted layer to thin compacted layer(N/C)with echocardiography and the correlation between C,N/C and the level of LVEF%,NT-ProBNP was also analyzed.7 patients were examined by echocardiography underwent delayed contrast enhancement MRI and the outcomes were analyzed.All the 36 patients were followed and tallied once readmission.Cox regression analysis was used to find the predictors of the prognosis of NVM.ResultThe common symptom of patients with NVM involves chest tightness,arrhythmia,chest pain and palpitation.Eight patients had hypertension,three patients had coronary heart disease and two patients had diabetes.ECG of 35 patients was abnormal in varying degrees,comprising complete left bundle branch block(8 cases),complete right bundle branch block(2 cases),Q wave abnormality(6 cases),III degree atrioventricular block(5 cases),atrial fibrillation(4 cases).Left ventricular ejection fraction of 6 patients was above 50%,26 patients between 30%and 50%,4 patients below 30%.7 patients were examined by echocardiography underwent delayed contrast enhancement MRI and 6 of them indicated noncompaction.Delayed contrast enhancement was seen in medio-ventricular septal(2 cases),left ventricle medial-layer myocardium(1 case),left ventricle subendocardial layer(1 case).Through Cox analysis,BMI,DCM,LogNT-ProBNP,troponin,CLBBB,LVEF and LVIDD are factors of prognosis in NVM patients,BMI is an independent prognostic factor(Hazard Ratio<1)which is a protective factor to cardiac events,while CLBBB is another independent prognostic factor(Hazard Ratio>1)which might lead to poor prognosis.The thickness of compacted layer(C)(0.63±0.25cm)and the ratio of thick noncompacted layer to thin compacted layer(N/C)(2.13±0.36)in echocardiogram failed to yield a significant association with the level of LVEF%and NT-ProBNP.ConclusionThe prevalent symptoms of patients with NVM comprise chest tightness and arrhythmia.Significant number of the patients also has hypertension.ECG is abnormal in most cases and low level of Left ventricular ejection fraction is common.The ratio of thick noncompacted layer to thin compacted layer measured in echocardiogram corresponds with the latest diagnostic criteria.Underwent delayed contrast enhancement MRI provides the basis for diagnosis and the lesion site.BMI and CLBBB are independent prognostic factors and prognosis is relatively good.