We sought to evaluate in vivo and in vitro left ventricular (LV) geometry and function in streptozotocin-induced diabetic rats and the possible role of the nitric oxide (NO) pathway.
Diabetes results ...in cardiac dysfunction; however, the specific abnormalities are unknown. Because decreased NO contributes to abnormal vascular function in diabetics, we hypothesized that NO pathway abnormalities may contribute to diabetic cardiomyopathy.
Control rats and those with non-insulin-dependent diabetes mellitus (NIDDM) underwent echocardiography, hemodynamic assessment, isolated heart perfusion and measurement of exhaled NO and LV endothelial constitutive nitric oxide synthase (ecNOS).
Diabetic rats had increased LV mass (3.3 +/- 0.6 vs. 2.6 +/- 0.3 g/g body weight BW, p < 0.001) and cavity dimensions (diastolic 2.0 +/- 0.1 vs. 1.8 +/- 0.2 cm/cm tibial length TL, p < 0.05). Diabetic rats had prolonged isovolumic relaxation time (IVRT) (40 +/- 8 vs. 26 +/- 6 ms, p < 0.0001), increased atrial contribution to diastolic filling (0.47 +/- 0.09 vs. 0.30 +/- 0.08 m/s, p < 0.0001), and elevated in vivo LV end-diastolic pressure (7 +/- 6 vs. 2 +/- 1 mm Hg, p = 0.04). Diabetic rats had increased chamber stiffness. Shortening was similar in both groups, despite reduced meridional wall stress in diabetics, suggesting impaired systolic contractility. Exhaled NO was lower in diabetic rats (1.8 +/- 0.2 vs. 3.3 +/- 0.3 parts per billion, p < 0.01) and correlated with Doppler LV filling. The ecNOS was similar between the groups.
Diabetic cardiomyopathy is characterized by LV systolic and diastolic dysfunction, the latter correlating with decreased exhaled NO. The NO pathway is intact, suggesting impaired availability of NO as contributor to cardiomyopathy.
Circulatory Shock Ammirati, Enrico; Oliva, Fabrizio; Frigerio, Maria ...
The New England journal of medicine,
02/2014, Letnik:
370, Številka:
6
Journal Article
Recenzirano
To the Editor:
In their review of circulatory shock, Vincent and De Backer (Oct. 31 issue)
1
report that hypoperfusion can be apparent through the skin (cold extremities), the kidney (low urinary ...output), and the brain (altered mental state). We believe that the liver should also be included in this list of key organs that are markers of shock. In cardiogenic shock, in which hypoperfusion is usually associated with increased central venous pressure, hepatomegaly can be clinically apparent by palpation, and abdominal discomfort due to stretching of the liver capsule may be a symptom. There is often an increase in levels . . .
Cyclosporin A (CsA) administered to actively growing young rats produces a high-turnover osteopenia. We investigated and compared the effect of CsA on the bone mineral metabolism in young rats with ...that of older rats, which have a lower rate of bone turnover. A group of 24 young (9 weeks) and 24 older (9 months) male Sprague-Dawley rats were orally administered 15 mg/kg of CsA or placebo daily for 24 days. Rats were weighed and serum assayed serially for bone gla protein (BGP), parathyroid hormone, ionized calcium, blood urea nitrogen, creatinine, and 1,25-dihydroxyvitamin D 1,25-(OH)2D. After sacrifice, histomorphometric analysis was performed on undecalcified proximal tibial metaphysis with double-fluorescent labeling. Serum BGP levels were significantly elevated in both young and older rats administered CsA, and 1,25-(OH)2D levels were significantly elevated in CsA-treated young rats more than in older rats. Body weight was significantly reduced in CsA-treated older rats. There were mild but significant alterations in renal function in both groups receiving CsA. In the most comprehensive examination to date of the effects of CsA on bone histomorphometry, both young (-44%) and older rats (-20%) lost significant amounts of trabecular bone compared to their respective controls. Bone loss in young rats was mainly due to a reduced number of trabecular; older rats lost mainly trabecular thickness. Microanatomic nodal studies were consistent with these results. These data demonstrate that although cancellous bone loss induced by CsA is more marked in young rats, older rats with slower bone turnover are also at risk.
We describe three cases of dynamic outflow obstruction complicating acute anterior myocardial infarction. Serial echocardiography suggests the intraventricular gradient results from basal ...hyperkinesis, the latter being a reciprocal response to the apical wall motion abnormality.
Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) are frequently utilized in patient's with suspected cerebral vascular ischemia. We describe a patient with suspected ...cerebral vascular ischemic event whom was found to have a mobile valvular mass by TTE and TEE. The lesion was unusual due to its rapid development over a period 6 months, which was documented on serial echocardiography. The mass was excised surgically and pathology showed a papillary fibroelastoma with extensive thrombus. The differential diagnosis of a cardiac valvular mass and the treatment of cardiac fibroelastomas are reviewed. In this case, both TTE and TEE were valuable in diagnosis and facilitating surgical management of a cardiac fibroelastoma.
To the Editor:
We wish to raise a note of caution about the use of anticoagulant agents to treat patients in whom protruding atherosclerotic plaques of the aortic arch have been diagnosed, because of ...the experience in our laboratories. We have followed 78 consecutive patients with protruding plaques of the thoracic aorta (>5 mm in thickness) for an average of 29 weeks; these patients have been treated with various anticoagulant and antiplatelet agents by their referring physicians.
1
Thirty-eight patients in this cohort received either intravenous heparin or warfarin. Four of them had a blue-toe syndrome that was associated with progressive . . .
TEE has assumed a pivotal role in the perioperative management of patients undergoing open-heart surgery. The information obtained influences important therapeutic decisions in thoracic aortic ...surgery, valvular surgery, and coronary artery bypass surgery. TEE also assists in determining the reason for failure to wean from cardiopulmonary bypass and allows rapid detection of the etiology of hypotension in the patient after surgery. Advances in technology have resulted in three-dimensional images of cardiac structures, and this will further enhance the usefulness of echocardiography for the surgeon. TEE should no longer be regarded as an imaging tool available only in academic centers, but should be routinely used by qualified operators in centers performing open-heart surgery.
OBJECTIVES
We sought to evaluate in vivo and in vitro left ventricular (LV) geometry and function in streptozotocin-induced diabetic rats and the possible role of the nitric oxide (NO) pathway.
...BACKGROUND
Diabetes results in cardiac dysfunction; however, the specific abnormalities are unknown. Because decreased NO contributes to abnormal vascular function in diabetics, we hypothesized that NO pathway abnormalities may contribute to diabetic cardiomyopathy.
METHODS
Control rats and those with non–insulin-dependent diabetes mellitus (NIDDM) underwent echocardiography, hemodynamic assessment, isolated heart perfusion and measurement of exhaled NO and LV endothelial constitutive nitric oxide synthase (ecNOS).
RESULTS
Diabetic rats had increased LV mass (3.3 ± 0.6 vs. 2.6 ± 0.3 g/g body weight BW, p < 0.001) and cavity dimensions (diastolic 2.0 ± 0.1 vs. 1.8 ± 0.2 cm/cm tibial length TL, p < 0.05). Diabetic rats had prolonged isovolumic relaxation time (IVRT) (40 ± 8 vs. 26 ± 6 ms, p < 0.0001), increased atrial contribution to diastolic filling (0.47 ± 0.09 vs. 0.30 ± 0.08 m/s, p < 0.0001), and elevated in vivo LV end-diastolic pressure (7 ± 6 vs. 2 ± 1 mm Hg, p = 0.04). Diabetic rats had increased chamber stiffness. Shortening was similar in both groups, despite reduced meridional wall stress in diabetics, suggesting impaired systolic contractility. Exhaled NO was lower in diabetic rats (1.8 ± 0.2 vs. 3.3 ± 0.3 parts per billion, p < 0.01) and correlated with Doppler LV filling. The ecNOS was similar between the groups.
CONCLUSIONS
Diabetic cardiomyopathy is characterized by LV systolic and diastolic dysfunction, the latter correlating with decreased exhaled NO. The NO pathway is intact, suggesting impaired availability of NO as contributor to cardiomyopathy.
PDF
