Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mortality rate for elective abdominal aortic operations remains between 3% and 8% despite careful hemodynamic monitoring, and half of these deaths are cardiac in origin. An extensive evaluation of ventricular function was performed during abdominal aortic operation to detect subtle abnormalities in systolic or diastolic ventricular function that could precipitate progressive ischemic cardiac injury. Twenty-three patients undergoing elective abdominal aortic operations (14 patients with abdominal aortic aneurysm [AAA] and nine patients with aortoiliac occlusive disease [AIOD] ) had hemodynamic and nuclear ventriculographic measurements performed preoperatively, during aortic clamping, and immediately after aortic declamping. No differences were found in the hemodynamic response to operation between patients with AAA or AIOD. Volume loading was performed at each time period to assess ventricular function. Myocardial performance (the relation between cardiac index and end-diastolic volume index) and systolic function (the relation between systolic blood pressure and end-systolic volume index) were depressed during aortic clamping (p less than 0.05), suggesting decreased contractility, but returned to baseline values after declamping. Diastolic compliance (the relation between pulmonary capillary wedge pressure and end-diastolic volume index) decreased after declamping (p less than 0.05), suggesting early myocardial ischemia. The decrease in diastolic compliance rendered pulmonary capillary wedge pressure a poor index of left ventricular preload after declamping. Higher pressures were required to maintain adequate diastolic volumes. Despite careful hemodynamic monitoring, potentially ischemic ventricular dysfunction was found during abdominal aortic operation.
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PMID:Cardiac dysfunction during abdominal aortic operation: the limitations of pulmonary wedge pressures. 370 40

ATP-sensitive K+ (K(ATP)) channels are abundantly expressed in the heart and may be involved in the pathogenesis of myocardial ischemia. These channels are heteromultimeric, consisting of four pore-forming subunits (Kir6.1, Kir6.2) and four sulfonylurea receptor (SUR) subunits in an octameric assembly. Conventionally, the molecular composition of K(ATP) channels in cardiomyocytes and pancreatic beta -cells is thought to include the Kir6.2 subunit and either the SUR2A or SUR1 subunits, respectively. However, Kir6.1 mRNA is abundantly expressed in the heart, suggesting that Kir6.1 and Kir6.2 subunits may co-assemble to form functional heteromeric channel complexes. Here we provide two independent lines of evidence that heteromultimerization between Kir6.1 and Kir6.2 subunits is possible in the presence of SUR2A. We generated dominant negative Kir6 subunits by mutating the GFG residues in the channel pore to a series of alanine residues. The Kir6.1-AAA pore mutant subunit suppressed both wt-Kir6.1/SUR2A and wt-Kir6.2/SUR2A currents in transfected HEK293 cells. Similarly, the dominant negative action of Kir6.2-AAA does not discriminate between either of the wild-type subunits, suggesting an interaction between Kir6.1 and Kir6.2 subunits within the same channel complex. Biochemical data support this concept: immunoprecipitation with Kir6.1 antibodies also co-precipitates Kir6.2 subunits and conversely, immunoprecipitation with Kir6.2 antibodies co-precipitates Kir6.1 subunits. Collectively, our data provide direct electrophysiological and biochemical evidence for heteromultimeric assembly between Kir6.1 and Kir6.2. This paradigm has profound implications for understanding the properties of native K(ATP)channels in the heart and other tissues.
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PMID:Is the molecular composition of K(ATP) channels more complex than originally thought? 1144 41

The prostaglandin I(2) (PGI(2)) analogue iloprost, a potent vasodilator and inhibitor of platelet activation, has traditionally been utilized in pulmonary hypertension and off-label use for revascularization of chronic critical lower limb ischemia. This study was designed to assess the effect of 72 hr iloprost infusion on systemic ischemia post-open elective abdominal aortic aneurysm (EAAA) surgery. Between January 2000 and 2007, 104 patients undergoing open EAAA were identified: 36 had juxtarenal, 15 had suprarenal, and 53 had infrarenal aneurysms, with a mean maximal diameter of 6.9 cm. The male-to-female ratio was 2.5:1, with a mean age of 71.9 years. No statistically significant difference was seen between the study groups with regard to age, sex, risk factors, American Society of Anesthesiologists (ASA) grade, or diameter of aneurysm repaired. All emergency, urgent, and endovascular procedures for aneurysms were excluded. Fifty-seven patients received iloprost infusion for 72 hr in the immediate postoperative period compared with 47 patients who did not. Patients were monitored for signs of pulmonary, renal, cardiac, systemic ischemia, and postoperative intensive care unit (ICU) morbidity. Statistically significantly increased ventilation rates (p=0.0048), pulmonary complication rates (p=0.0019), and myocardial ischemia (p=0.0446) were noted in those patients not receiving iloprost. These patients also had significantly higher renal indices including estimate glomerular filtration rate changes (p=0.041) and postoperative urea level rises (p=0.0286). Peripheral limb trashing was noted in five patients (11.6%) in the non-iloprost group compared with no patients who received iloprost. Increased rates of transfusion requirements and bowel complications were noted in those who did not receive iloprost, with their ICU stay greater than twice that of iloprost patients. All-cause morbidity affected 67% of patients not receiving iloprost compared to 40% who did. Survival rates were significantly better with iloprost than without in both 30-day (p=0.009) and 5-year cumulative (p=0.0187) survival. Iloprost infusion for 72 hr after open AAA repair was associated with improved systemic perfusion and decreased systemic ischemia. Patients had a significant survival benefit at 30 days and 5 years and significantly improved renal, cardiac, and respiratory function.
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PMID:Six years' experience with prostaglandin I2 infusion in elective open repair of abdominal aortic aneurysm: a parallel group observational study in a tertiary referral vascular center. 1899 65

With the development of endovascular aneurysm repair, abdominal aortic aneurysms with short infrarenal necks (< or =10 mm, AAASN) are considered juxtarenal aneurysms. Minimally invasive treatment consists of hybrid procedures or fenestrated endografts. We present our experience with direct aortic repair for AAASN performed via a total laparoscopic approach. Data are expressed as median values with extremes. From February 2002 to December 2007, 32 patients had total laparoscopic AAASN repair. Length of the infrarenal aortic neck was 5 mm (0-10). Median age of the 29 men and three women was 70 years (range 50-84). Nine patients presented with preoperative grade 1 renal insufficiency (28.1%). The procedure was totally laparoscopic in 30 patients (93.7%). Aortic approaches included left retrorenal (n = 24) and transperitoneal left retrocolic (n = 8) exposures. Median operative and clamping times were 270 (range 215-410) and 83 (range 36-147) min, respectively. Aortic clamping was suprarenal in 14 cases (43.7%), with suprarenal clamping time of 24 min (range 9-37). Median blood loss was 850 mL (range 215-2,400). Thirty-day mortality was 3.1% (one patient died from myocardial infarction). Two patients presented with severe systemic complications (6.4%, postoperative coagulopathy with hemorrhagic syndrome, pneumopathy). Seventeen patients developed mild or moderate systemic nonlethal complications (53.1%): transient renal insufficiencies (n = 12), grade 1 ischemic colitis (n = 1), surrenal insufficiency (n = 1), myocardial ischemia (n = 1), and cardiac arythmia (n = 2). One patient was reoperated for an intestinal obstruction. Liquid diet was reintroduced after 1 day (range 1-13). Most patients were ambulatory by day 3 (range 2-17). Median lengths of stay were 48 hr (range 12-552) in the intensive care unit and 10 days (range 4-37) in the hospital. With a median follow-up of 27 months (range 1-50), 28 patients are alive, with complete recovery without graft anomalies. Three patients died, from pneumopathy (n = 1) and carcinoma (n = 2), respectively, at 29, 19, and 44 months' follow-up. Two patients presented stable juxta-renal aortic dilation <35 mm. Total laparoscopic juxtarenal AAA repair is feasible and worthwhile for patients with AAASN. Short- and midterm results match well with those of open surgery. Total laparoscopic repair in AAASN reduces the trauma of extensive surgical approaches. Based on these encouraging early results, we elected to perform laparoscopy whenever possible in good surgical risk patients with AASN.
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PMID:Total laparoscopic repair of abdominal aortic aneurysm with short proximal necks. 1913 10