Depressed recovery of subendocardial perfusion in persistent heart failure after complete revascularisation in diabetic patients with hibernating myocardium
ABSTRACT To investigate the relation between myocardial perfusion and heart failure (HF) status after revascularisation in patients with HF due to hibernating myocardium (HM) in diabetic and non-diabetic subjects.
31 diabetic and 33 non-diabetic subjects with HF due to HM, who were already scheduled for complete revascularisation, were studied. Before and after revascularisation, left ventricular function and regional perfusion in subendocardial and subepicardial portions of the left ventricular wall were evaluated.
Before revascularisation, left ventricular function and regional perfusion were similar in diabetic and non-diabetic subjects. At 6 months after revascularisation, subepicardial perfusion was markedly improved both in diabetic and non-diabetic subjects. However, subendocardial perfusion was markedly improved only in non-diabetic subjects and was little changed in diabetic patients. Thus, subendocardial perfusion was much lower in diabetic than non-diabetic subjects. Left ventricular function was improved more in non-diabetic than in diabetic subjects. Persistent HF was found much more often in diabetic than non-diabetic subjects. At multivariate analysis, subendocardial perfusion at 6 months independently contributed to persistent HF.
This study describes the intramural heterogeneity of recovery of myocardial perfusion with depressed improvement in the subendocardial portion and its relation with persistent HF after complete revascularisation in diabetic patients with HF due to HM.
Article: Neovascularization in diabetes[Show abstract] [Hide abstract]
ABSTRACT: Diabetes and its complications are a major public health burden in the developed world. The major cause of diabetic complications is abnormal growth of new blood vessels. This dysfunctional neovascularization results in significant morbidity and mortality in patients with diabetes and, as such, is a major focus of basic and clinical investigation. It has become clear that hyperglycemia disrupts tissue-level signaling in response to hypoxia and ischemia, impairs the vasculogenic potential of circulating stem cells and fundamentally alters the structure and function of key neovascularization proteins, including hypoxia-inducible factor-1. These mechanistic and pathophysiologic studies have revealed new therapeutic targets to restore normal neovascularization and to ameliorate and prevent diabetic vascular complications.Expert Review of Endocrinology & Metabolism 12/2009; 5(1):99-111. DOI:10.1586/eem.09.57
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ABSTRACT: The initiation of ventricular diastole is an energy-dependent phase of cardiac cycle. Delayed onset of left ventricular (LV) relaxation has been proposed to identify myocardial ischemia. Diabetes mellitus (DM) is known to be associated with coronary microangiopathy, but its influence on LV early relaxation is not established. Ninety-two subjects consisting of 70 DM patients without overt cardiac disease and 22 normal controls were evaluated. Using strain rate imaging, time from R-wave on the electrocardiogram to onset of LV relaxation (Tr) was measured at rest and peak exercise. Using myocardial contrast echocardiography, myocardial blood flow (MBF) was measured at rest and peak exercise, enabling MBF reserve. Tr at rest was similar between DM patients and controls, but Tr at peak exercise was significantly longer in DM patients than controls. MBF reserve was significantly reduced in DM patients compared with controls. There was a significant negative correlation between Tr at peak exercise and MBF reserve. In a multivariate analysis, MBF reserve was an independent determinant of Tr at peak exercise. This study demonstrates that DM patients have exercise-induced delayed onset of LV relaxation in association with impaired coronary microcirculatory function in the absence of coexistent heart disease.Journal of cardiac failure 03/2010; 16(3):211-7. DOI:10.1016/j.cardfail.2009.10.024 · 3.07 Impact Factor
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ABSTRACT: OBJECTIVE: To identify the predictive factors of myocardial stunning as assessed by the drop in post-stress Left Ventricular Ejection Fraction (LVEF) in patients with a recent history of myocardial infarction (MI). METHODS: We prospectively included 215 consecutive patients admitted for acute MI who underwent percutaneous coronary intervention with a greater than or equal to grade-3 TIMI flow in the culprit vessel. Six months after discharge, a post-stress/rest (99m)Tc-sestamibi gated SPECT was performed. The perfusion score was evaluated visually using a 17-segment model. The LVEF drop was considered significant if the post-stress LVEF was ≥5 % below the rest LVEF (QGS(®) software). RESULTS: A post-stress LVEF drop was observed in 51 (24 %) patients. Patients with an LVEF drop were more likely than patients with a stable post-stress LVEF to have diabetes (22 % vs. 10 %, p = 0.048), significant ischemia (SDS > 2) (51 % vs. 28 % p = 0.003) and higher rest LVEF [62 % (56-69) vs. 56 % (49-63) p < 0.001]. In contrast, summed rest score, related to infarct size, did not differ between the groups. Multivariate logistic regression analysis identified SDS > 2 (OR 3.78, 95 % CI 1.8-7.92, p < 0.001), diabetes (OR 3.35, 95 % CI 1.33-8.49; p = 0.011) and rest LVEF (OR 1.08, 95 % CI 1.04-1.12, p < 0.001) as independent explanatory variables of an LVEF drop. CONCLUSION: In patients with recent MI and post-procedural grade-3 TIMI flow, ischemia and diabetes were independent predictive factors of myocardial stunning. The higher incidence of reversible perfusion abnormalities validates the model of myocardial stunning in the post-MI period, and excludes the potential involvement of myocardial necrosis.Annals of Nuclear Medicine 10/2012; 27(2). DOI:10.1007/s12149-012-0661-9 · 1.51 Impact Factor