Aldosterone receptor antagonism induces reverse remodeling when added to angiotensin receptor blockade in chronic heart failure.

OBJECTIVES: The objective of this study was to determine if adding spironolactone to an angiotensin II receptor blocker improves left ventricular (LV) function, mass, and volumes in chronic heart failure. BACKGROUND: Add-on spironolactone therapy substantially improves clinical outcomes among patients with severe heart failure (HF) on standard therapy. However, the value of combining spironolactone with an angiotensin II receptor blocker on LV reverse remodeling in mild-to-moderate systolic HF is unclear. METHODS: Fifty-one systolic HF patients with left ventricular ejection fraction (LVEF) <40% were randomly assigned to receive 1-year treatment of candesartan and spironolactone (combination group) or candesartan and placebo (control group). Reverse remodeling was assessed by serial cardiac magnetic resonance imaging and echocardiographic tissue Doppler imaging (TDI). RESULTS: There were significant improvements in LVEF (35 +/- 3% vs. 26 +/- 2%, p < 0.01) and reduction of LV end-diastolic volume index (121 +/- 16 ml/m2 vs. 155 +/- 14 ml/m2, p = 0.001), end-systolic volume index (88 +/- 17 ml/m2 vs. 120 +/- 15 ml/m2, p < 0.0005), and LV mass index (81 +/- 6 g/m2 vs. 93 +/- 6 g/m2, p = 0.002) in the combination group at 1 year. In addition, there was significant increase in peak basal systolic velocity and strain by TDI, decrease in index of filling pressure, and increase in cyclic variation integrated backscatter. In the control group, there were no significant changes in all these parameters after 1 year. CONCLUSIONS: The addition of spironolactone to candesartan has significant beneficial effects on LV reverse remodeling in patients with mild-to-moderate chronic systolic HF.

Strain rate imaging differentiates transmural from non-transmural myocardial infarction: a validation study using delayed-enhancement magnetic resonance imaging.

OBJECTIVES: The aim of this study was to determine if strain rate imaging (SRI) correlates with the transmural extent of myocardial infarction (MI) measured by contrast-enhanced magnetic resonance imaging (Ce-MRI). BACKGROUND: Identification of the transmural extent of myocardial necrosis and degree of non-viability after acute MI is clinically important. METHODS: Tissue Doppler echocardiography with SRI and Ce-MRI were performed in 47 consecutive patients with a first acute MI between days 2 and 6 and compared to 60 age-matched healthy volunteers. Peak myocardial velocities and peak myocardial deformation strain rates were measured. Location and size of the infarct zone was confirmed by Ce-MRI using the delayed enhancement technique with a 16-segment model. RESULTS: Contrast-enhanced MRI identified transmural infarction in 21 patients, non-transmural infarction in 15 (mean transmurality of infarct 72.3 +/- 10.6%), and another 11 patients with subendocardial infarction (<50% transmural extent of the left ventricular wall). Peak systolic strain rate (SRs) of the transmural infarction segments was significantly lower compared to normal myocardium or with non-transmural infarction segments (both p < 0.0005). A cutoff value of SRs >-0.59 s(-1) detected a transmural infarction with high sensitivity (90.9%) and high specificity (96.4%), and -0.98 s(-1) >SRs >-1.26 s(-1) distinguished subendocardial infarction from normal myocardium with a sensitivity of 81.3% and a specificity of 83.3%. CONCLUSIONS: Peak myocardial deformation by SRI can differentiate transmural from non-transmural MI, and it allows noninvasive determination of transmurality of the scar after MI and thereby the extent of non-viable myocardium.

Effect of N-acetylcysteine for prevention of contrast nephropathy in patients with moderate to severe renal insufficiency: a randomized trial.

BACKGROUND: The effect of N-acetylcysteine (NAC) to prevent contrast nephropathy (CN) in patients with moderate to severe renal insufficiency undergoing coronary angiography or interventions is not clear. METHODS: This is a prospective, open-label, randomized, controlled trial. Ninety-one consecutive patients with a serum creatinine level of 1.69 to 4.52 mg/dL (149 to 400 micromol/L) undergoing coronary procedures were recruited and randomly assigned to administration of either oral NAC, 400 mg, thrice daily the day before and day of the contrast procedure (the NAC group) or no drug (the control group). Serum creatinine was measured before and 48 hours after contrast exposure. The primary end point of this study was the development of CN, defined as an increase in serum creatinine concentration of 0.5 mg/dL or greater (> or =44 micromol/L) or a reduction in estimated glomerular filtration rate (GFR) of 25% or greater of the baseline value 48 hours after the procedure. RESULTS: There were no significant differences between the 2 groups (46 patients, NAC group; 45 patients, control group) in baseline characteristics or mean volume of contrast agent administered. Six patients (13.3%) in the control group and 8 patients (17.4%) in the NAC group developed CN (P = 0.8). Serum creatinine levels increased from 2.27 +/- 0.54 to 2.45 +/- 0.65 mg/dL (201 +/- 48 to 217 +/- 57 micromol/L; P = 0.003) in the NAC group and 2.37 +/- 0.61 to 2.40 +/- 0.70 mg/dL (210 +/- 54 to 212 +/- 62 micromol/L; P = 0.6) in the control group. The increase in serum creatinine levels between the 2 groups had no difference (P = 0.7). Estimated GFR decreased from 30.3 +/- 8.4 to 28.1 +/- 8.4 mL/min (P = 0.01) in the NAC group and 28.4 +/- 8.6 to 27.5 +/- 8.8 mL/min (P = 0.3) in the control group. The decline in estimated GFR between the 2 groups had no difference (P = 0.7). CONCLUSION: In the current study, oral NAC had no effect on the prevention of CN in patents with moderate to severe renal insufficiency undergoing coronary angiography or interventions. However, the sample size of our present study is small. Our findings highlight the need for a large-scale, randomized, controlled trial to determine the exact beneficial effect of NAC.