Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acute mitral regurgitation (MR) is present in 10% of patients presenting with cardiogenic shock. To stabilize these patients, intra-aortic balloon pumping (IABP) is recommended, but the mechanism of IABP support in these patients is unknown. This animal study was designed to describe the hemodynamic effect of intra-aortic balloon pumping during cardiogenic shock induced by acute MR. In eight calves, left ventricular pressure-volume loops, aortic and left atrial pressure, and aortic, carotid artery, and coronary blood flow were recorded. Acute MR (range 36%-79%) was created by placing a metal cage in the mitral valve. Hemodynamic data was obtained at control, during acute MR, and during acute MR with 1:1 IABP support. Acute MR caused a decrease in cardiac output (-32%, P = 0.018), blood pressure, and carotid artery flow, whereas left ventricular output (+127%, P = 0.018), end-diastolic volume, and left atrial pressure all significantly increased. Stroke work, ejection fraction, and coronary blood flow were not significantly changed, and no signs of ischemia were seen on the ECG. The IABP raised average cardiac output by 31% (P = 0.012) and significantly raised blood pressure and flow to the brain while decreasing systemic vascular resistance. Left ventricular function and mean coronary blood flow did not change, but diastolic coronary flow became more important as shown by the increase in diastolic fraction from 64% to 95%. (P = 0.028). Average MR dropped by 7.5% (P = 0.025). In conclusion, application of the IABP during acute MR lowers aortic impedance, resulting in less MR and more output toward the aorta without changing left ventricular function.
 ...
PMID:Intra-aortic balloon pumping in acute mitral regurgitation reduces aortic impedance and regurgitant fraction. 1268 44

Acute mitral regurgitation (AMR), a known complication of acute coronary syndromes, is usually associated with posterior papillary muscle dysfunction/rupture. In severe cases, management of AMR requires surgical intervention. Reversible severe AMR in patients in the absence of left ventricular systolic dysfunction and coronary artery stenosis may result from processes which cause transient subendocardial ischemia, such as intermittent episodes of hypotension or coronary artery vasospasm. We present two cases of reversible transient AMR due to subendocardial and/or endocardial ischemia, both of which offer insight into the mechanism of transient severe AMR.
...
PMID:Mechanistic insights into transient severe mitral regurgitation. 2698 31