Objective To report a reliable left heart failure model in sheep using selected ligation of the diagonal branch. Methods Four male sheep were used. After a left anterior thoracotomy in sheep, the diagonal branch of coronary artery was ligated at a point approximately 40% of the distance from the apex to the base of the heart. Hemodynamic and echocardiography measurements were done preligation, 30 minutes and 7 days after the coronary artery of diagonal branch ligation. The electrocardiograms were obtained as needed, and cardiac function was also evaluated. The sheep were killed for postmortem examination of their hearts. Results Four sheep survived the experimental procedures. Comparing with before surgery, systemic arterial blood pressure and cardiac output were decreased, pulmonaryartery systolic pressure, pulmonary capillary wedge pressure and central venous pressure were increased at 30 min and 7 days after selected ligation of the coronary artery of diagonal branch; left ventricular end-diastolic dimension and left ventricular end-systolic dimension were increased; left ventricular ejection fraction and left ventricular fractional shortening were also decreased (Plt;0.05). Conclusion A reliable ovine model of left ventricular failure using selected ligation of the diagonal branch of the coronary artery can be achieved. This animal model is comparable to the clinical correlation.
ObjectiveTo investigate the effect of noninvasive positive-pressure ventilation for elderly patients with chronic obstructive pulmonary disease (COPD) combined with left heart failure. MethodsA total of 152 patients (70-85 years old) diagnosed with COPD combined with left heart failure and treated in our hospital between June 2011 and January 2015 were randomly divided into trial group (noninvasive positive-pressure ventilation with routine treatment, n=76) and control group (routine treatment, n=76). Respiratory rate, heart rate, blood pressure, pH, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of oxygen (PaO2) and left ventricular ejection fraction (LVEF) were analyzed and compared between the two groups after treatment. We did t-test to analyze the difference of these indexes between the two groups statistically. ResultsRespiratory rate, heart rate and PaCO2 in both of the two groups after the treatment were significantly lower than those before the treatment (P<0.001), while PaO2 and LVEF in both of the two groups after the treatment were significantly higher than those before the treatment (P<0.001). The systolic pressure and diastolic pressure in both of the two groups after the treatment didn't differ much from those before the treatment (P>0.05). The pH value after the treatment increased only in the trial group compared with that before the treatment (P<0.05). The respiratory rate, heart rate, pH value, PaO2, PaCO2 and LVEF after the treatment in trial group were meliorated compared with those in the control group (P<0.05). ConclusionTreatment with noninvasive positive-pressure ventilation for elderly patients with COPD combined with left heart failure is more efficient than the routine treatment.