Assessment of left ventricular and atrial diastolic function using two-dimensional (2D) strain imaging in patients with ß-thalassemia major.

BACKGROUND: ß-thalassemia major is a unique disease characterized by early severe diastolic dysfunction, due to iron myocardial deposition alone, while left ventricular systolic dysfunction and failure seem to be multifactorial in aitiology. OBJECTIVES: The purpose of this study was to investigate left ventricular diastolic dysfunction using a new echo index as speckle tracking in comparison with the conventional methods. MATERIAL AND METHODS: Eighty-eight consecutive patients (38 male, 50 female) aged 36 ± 8.2 yr with ß-thalassemia major and preserved LV ejection fraction (LVEF>55%) were studied. Patients were divided into two groups according to the E mitral/E mitral annulus ratio (E/E'): group A patients with E/E' ratio ≤8 and group B patients with E/E' >8. Cutoff value of eight was used to separate patients with normal and abnormal diastolic function. All subjects were studied thoroughly by tissue Doppler echocardiography as also by 2D left ventricular and atrial strain imaging 2-4 d following blood transfusion. Blood samples were also taken for plasma BNP measurements at the same time. RESULTS: Left atrial volumes(LAV max, LAV min) as also left atrial index were significantly higher in patients with diastolic dysfunction compared with patients without diastolic dysfunction(LAV max: 57.6 ± 19.4 vs. 71.3 ± 22.9, P < 0.01,LAV min: 20.2 ± 11.4 vs. 33.9 ± 18, P < 0.01, LAVI: 37.66 ± 12.18 vs. 47.13 ± 14.77, P < 0.01). Radial 2D strain (RS) and peak atrial 2D strain (AS) were significantly reduced in patients with suspected diastolic dysfunction compared with patients without diastolic dysfunction (RS: 43.48 ± 13.92 vs. 35.58 ± 11.32, P < 0.05; AS: 36.36 ± 8.45 vs. 29.85 ± 9.25, P < 0.01). Using ROC analysis, peak atrial 2D strain at a cutoff of 41.1 cm/s was highly accurate (AUC: 0.66, P < 0.05 in ruling out diastolic dysfunction (E/E'<8) with a sensitivity of 90% and a specificity of 81%. CONCLUSIONS: B-thalassemic major patients with preserved left ventricular systolic function had impaired left atrial function at the longitudinal axis and left ventricular function at the radial axis. The new echo markers have better prognostic value than the traditional echo indexes in detecting latent diastolic dysfunction in ß-thalassemia major, earlier than E/E' ratio.

An amyloidogenic determinant in N-terminal pro-brain natriuretic peptide (NT-proBNP): Implications for cardiac amyloidoses.

Deposition of amyloid in the atria (isolated atrial/cardiac amyloid) is fairly common in the aging heart. It consists of amyloid fibrils, formed both by atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) and the precursor molecule of ANP, proANP. This study examines whether amyloidogenic determinants (short peptides/amyloid forming favoring regions) exist in the sequence of NT-proBNP, the N-terminal part of proBNP, and if these determinants form amyloid-like fibrils in vitro. We have predicted a possible amyloidogenic determinant in the sequence of the NT-proBNP, and we conclusively show, after its synthesis, that it forms amyloid-like fibrils in vitro, utilizing transmission electron microscopy, X-ray diffraction, attenuated total reflectance Fourier-transform infrared spectroscopy, and polarizing microscopy. Thus, for the first time, in this study, a possible biological role is attributed to a certain, specific part of this important cardiac prohormone/natriuretic peptide, which acts as an important biomarker indicative of heart failure. Its possible direct involvement in isolated cardiac amyloidosis, atrial fibrillation, and other types of cardiac amyloidoses is indicated and discussed. Since these cardiac hormones and their prohormones play key roles in cardiovascular homeostasis through natriuresis, diuresis, vasorelaxation, and inhibition of renin and aldosterone secretion (pathophysiology of hypertension and cardiovascular regulation), we also try to suggest these specific, short peptides as possible future structural targets of efforts toward inhibiting formation of natriuretic peptide(s) amyloid.

Predictive value of B-type natriuretic peptides in detecting latent left ventricular diastolic dysfunction in beta-thalassemia major.

BACKGROUND: Beta-thalassemia major is a unique disease characterized by early diastolic dysfunction, related exclusively to iron myocardial deposition. N-terminal-proBNP(amino-terminal) (NT-proBNP) and B-type natriuretic peptide (BNP) are sensitive biomarkers for the detection of asymptomatic left ventricular (LV) dysfunction, and they have important diagnostic and prognostic implications. Using beta-thalassemia as a model disease with isolated diastolic dysfunction, we sought to investigate the predictive value of NT-proBNP and BNP levels in comparison with the conventional and new Doppler echocardiography indexes in detecting this disorder. METHODS: Seventy beta-thalassemia major patients (mean age 27.2 +/- 12.5 years) with normal LV systolic function (mean LV ejection fraction = 59% +/- 6.8%), and 50 healthy age-matched adults (control group: mean age 25.5 +/- 10.1 years, mean LV ejection fraction = 60% +/- 4.5%) were included. All subjects were studied thoroughly by tissue Doppler echocardiography and blood samples were taken for plasma NT-proBNP and BNP measurements at the same time. To examine LV diastolic function, patients were divided in 3 groups according to the E mitral/E mitral annulus ratio (E/E'): group A, patients without diastolic dysfunction: E/E' ratio <8; group B, patients with suspected diastolic dysfunction: E/E' ratio 8 to 15; group C, patients with documented diastolic dysfunction: E/E' ratio, >15. RESULTS: NT-proBNP and BNP levels were higher in thalassemic patients compared with the control group (NT-proBNP levels: 80 +/- 19 vs 21 +/- 4 pg/mL, P < .001; BNP levels: 34 +/- 6 vs 9 +/- 3 pg/mL, P < .001). NT-proBNP levels showed a statistically significant increase in group C in comparison to groups A and B, which was also detected between groups A and B (A vs B: P < .05). BNP levels were also significantly increased in group C in comparison to the other 2 groups, but there was no statistically significant difference between groups A and B. Using receiver operating characteristic analysis, NT-proBNP at a cut point of 49.2 pg/mL was highly accurate (area under curve: 0.97, P < .001) in ruling out diastolic dysfunction (E/E' <8) with a sensitivity of 93.7% and a specificity of 89.6%. CONCLUSIONS: BNP and NT-proBNP levels are significantly increased in documented left ventricular diastolic dysfunction, while NT-proBNP seems to have better predictive value in detecting latent left ventricular diastolic dysfunction in beta-thalassemia major.

NT-proBNP levels and diastolic dysfunction in beta-thalassaemia major patients.

BACKGROUND: The early diagnosis and treatment of heart failure in beta-thalassaemic patients is related to survival. Iron alone or in combination with other factors causes diastolic dysfunction, which usually precedes systolic dysfunction. NT-proBNP is a sensitive biomarker of ventricular dysfunction. AIM: To evaluate NT-proBNP in non heart failure beta-thalassaemic patients. METHODS: Fifty-two beta-thalassaemia major patients (mean age: 27.2+/-12.5 years) with normal LV systolic function, underwent NT-proBNP measurement and a thorough Doppler-echocardiographic and pulsed tissue-Doppler study, 4 days following blood transfusion. Fifty-two age matched healthy controls were also studied. RESULTS: NT-proBNP and E/E' ratio were increased in thalassaemic patients compared with controls [(469+/-171 vs 262+/-51 pmol/l, p<0.001) and (10.8+/-4.0 vs 6.6+/-1.1, p<0.001)] and were well correlated (r: 0.54, p<0.01). Although NT-proBNP levels were increased in patients with higher E/E' ratios (E/E' <8: 354+/-119, 8-15: 516+/-177, >15: 565+/-114 pmol/l, ANOVA p: 0.002) this increase only became statistically significant in the 3rd decade of life, while E/E' ratio increased in the 4th decade. CONCLUSION: NT-proBNP increases in beta-thalassaemia major patients and is related to age and LV diastolic dysfunction. NT-proBNP appears to be an early biomarker of LV diastolic dysfunction, compared with the conventional Echo-Doppler indexes.

Relation of elevated C-reactive protein and interleukin-6 levels to left atrial size and duration of episodes in patients with atrial fibrillation.

Previous studies have demonstrated inflammation to be a risk factor in patients with atrial fibrillation (AF). In this prospective study of 90 patients with persistent and permanent AF and 46 controls, we found increased C-reactive protein (CRP) and interleukin-6 levels in patients with AF compared with controls (p <0.001). Multivariate analysis revealed CRP to be an independent predictor of AF (p = 0.01). Left atrial diameter was positively related to CRP and interleukin-6 (p <0.001, R = 0.37; p <0.001, R = 0.46, respectively) and negatively related to left ventricular function. Interleukin-6 levels were positively related to AF duration before cardioversion (p = 0.02). Elevation of CRP and interleukin-6 suggest a role of inflammation in AF, and the relation of CRP and interleukin-6 to left atrial size and AF duration before cardioversion indicates that inflammation may participate in the process of atrial remodeling.

Preinfarction angina does not alter infarct size and in hospital outcome after acute myocardial infarction with ST elevation.

BACKGROUND: Preinfarction angina has been reported to limit infarct size, in a manner analogous to experimental preconditioning. However, other studies have reported inconsistent results. We aimed to investigate prospectively the role of preinfarction angina on infarct size and in hospital outcome. METHODS: Ninety-nine patients were divided into three groups according to the timing of angina: the group "< 48 h" reported angina within the last 48 h, the group "> 48 h" earlier than 48 h and the group "acute" no angina before infarction. Myocardial injury was estimated by creatine kinase, creatine kinase-MB, troponin I and C-reactive protein. In hospital events included death, recurrent ischemia, congestive heart failure and atrioventricular block. RESULTS: Clinical characteristics, thrombolysis administration and the magnitude of enzymes released were not statistically different among the three groups: peak creatine kinase was 2139+/-1714 U/l for the >48 h group, vs. 2344+/-1634 U/l for the acute group, vs. 2209+/-1384 U/l for the <48 h group (p=0.88). Peak creatine kinase-MB was 124+/-104 U/l for the >48 h group, vs. 168+/-182 U/l for the acute group, vs. 154+/-108 U/l for the <48 h group (p=0.62). Peak troponin I, peak C-reactive protein and in hospital outcome also did not differ statistically in the three groups; p=0.5, p=0.45. CONCLUSIONS: Infarct size estimated by cardiac enzymes and by the marker of C-reactive protein, as well as in hospital clinical prognosis are not different in patients with and without preinfarction angina. It seems, therefore, that preinfarction angina confers ischemic conditions inadequate to mimic preconditioning.

Management of inadvertent left ventricular permanent pacing.

Inadvertent implantation of a pacemaker lead in the left ventricle is an uncommon complication. We report a case of a permanent pacemaker lead inadvertently placed through the left subclavian artery, across the aortic valve into the left ventricle. A chest X-ray one month after the procedure showed an unusual course of the lead and a 12-lead ECG and a transthoracic echocardiogram confirmed the diagnosis. The patient refused surgical removal and remained on full anticoagulation. No clinical events were recorded during a 3-year follow-up. In such cases we propose life-long full anticoagulation as an alternative to surgical lead extraction.

The effect of acute administration of statins on coronary microcirculation during the pre-revascularization period in patients with myocardial infraction.

UNLABELLED: The beneficial effects of statin pretreatment as well as of staccato reperfusion (SR) on myocardium have been demonstrated in patients undergoing cardiac interventions. In this study, we compared the effects of the acute statin administration prior to percutaneous coronary intervention (PCI) with the effects of staccato or abrupt reperfusion on coronary microcirculation in patients with myocardial infarction (MI). METHODS: We randomly assigned 47 patients who had ST-elevation or non-ST-elevation MI 48 h prior to PCI, into three groups: staccato reperfusion (consisting of 6 periods of 10-s balloon inflation/deflation) plus statin therapy (SRSG), statin therapy plus abrupt reperfusion (SG), and abrupt reperfusion alone (ARG). Myocardial contrast echocardiography (MCE) was performed to assess the blood volume (A), velocity (ß) and flow (A × ß) of the segments associated with the PCI-treated artery the day following intervention and 30 days after. LV end-diastolic (EDV) and systolic volumes (ESVs), wall motion score index (WMSI) were evaluated. RESULTS: Compared to ARG, SRSG and SG resulted in a greater improvement in A, ß and A × ß (F = 20.6, p < 0.001 for A, F = 3.5, p = 0.03 for ß and F = 11.3, p < 0.001 for A × ß for the overall effect of intervention) as well as a greater decrease of WMSI, EDV and ESV (p < 0.01) one month post-PCI. The changes of all echocardiography markers were greater in SRSG than SG (p < 0.01). The % changes in ESV correlated with the corresponding % changes in MCE indices in SRSG and SG (p < 0.05). CONCLUSION: The acute statin administration prior to reperfusion either alone or in synergy with staccato reperfusion ameliorates coronary microcirculatory dysfunction in patients with myocardial infarction.