Claudio Bilato

Postconditioning during coronary angioplasty in acute myocardial infarction: the POST-AMI trial

BACKGROUND Postconditioning (PC) has been suggested to reduce myocardial damage during primary percutaneous coronary intervention (PPCI), nevertheless clinical experience is limited. We aimed to explore the cardioprotective effect of PC using cardiac magnetic resonance (CMR) in ST-elevation myocardial infarction (STEMI) patients treated by PPCI. METHODS A total of 78 patients with first STEMI (aged 59±12 years) referred for PPCI, were stratified for STEMI location and randomly assigned to conventional PPCI or PPCI with PC. All patients, with occluded infarct related artery and no collateral circulation, received abciximab intravenously before PPCI. After reperfusion by effective direct stenting, control subjects underwent no further intervention, while in treated patients PC was performed within 1 min of reflow by 4 cycles of 1-minute inflation and 1-minute deflation of the angioplasty balloon. Primary end-point was infarct size (IS) reduction, expressed as percentage of left ventricle mass assessed by delayed enhancement on CMR at 30±10 days after index PPCI. RESULTS All baseline characteristics but diabetes (p=0.06) were balanced between groups. Postconditioning patients trended toward a larger IS compared to those treated by standard PPCI (20±12% vs 14±10%, p=0.054). After exclusion of diabetics, PC group still showed a trend to larger IS (p=0.116). Major adverse events seem to be more frequent in PC group irrespective to diabetic status (p=0.053 and p=0.080, respectively). CONCLUSIONS This prospective, randomized trial suggests that PC did not have the expected cardioprotective effect and on the contrary it might harm STEMI patients treated by PPCI plus abciximab. (Clinical Trial Registration-unique identifier: NCT01004289).

Prevalence, Functional Impact, and Mortality of Atrial Fibrillation in an Older Italian Population (from the Pro.V.A. Study)

The prevalence of atrial fibrillation (AF) is increasing in older patients faster than that of any other arrhythmia. AF is associated with increased morbidity and mortality. Data on AF in European populations are scarce. The aim of this study was to determine the prevalence and potential predictors of AF and to assess its impact on physical function and mortality in a representative sample of an Italian population >or=65 years of age. One thousand five hundred ninety-nine participants in the Pro.V.A. study, an observational cohort study of Italian subjects >or=65 years old, were assessed for health status, disability, and presence of AF at baseline and at a 4-year follow-up visit. After weighting, prevalence of AF at baseline was 7.4% and increased with advancing age. In subjects with AF, prevalences of stroke, coronary heart disease, peripheral artery disease, cognitive impairment, and physical disability were significantly higher (p <0.01) than in those without AF. In patients with AF, 34% had heart failure compared to 5.3% of those without AF (p <0.0001). In multivariate logistic regression, heart failure was associated with a fivefold risk of AF (odds ratio 5.09, 95% confidence interval 3.20 to 8.11). In Cox analysis, AF was an independent risk factor for mortality. After adjustment for potential confounders, the hazard ratio for mortality associated with AF was 1.47 (95% confidence interval 1.08 to 1.99). In conclusion, in subjects >or=65 years old, AF is strongly associated with heart failure, is an independent risk factor for mortality, and, in the presence of physical disability, could be considered a severity measurement of disability.

LAD Coronary Artery Myocardial Bridging and Apical Ballooning Syndrome

OBJECTIVES This study sought to evaluate the prevalence and potential role of myocardial bridging in the pathogenesis of apical ballooning syndrome (ABS). BACKGROUND ABS is characterized by reversible left ventricular dysfunction, frequently precipitated by a stressful event, but the pathogenesis remains still unclear. METHODS Forty-two consecutive patients (40 female, mean age 66 ± 7 years) with ABS underwent echocardiography, cardiac magnetic resonance, coronary angiography (CA) with intravascular ultrasound, and computed tomography angiography (CTA). Myocardial bridging was diagnosed by CA when a dynamic compression phenomenon was observed in the coronary artery and by CTA when a segment of coronary artery was completely (full encasement) or incompletely (partial encasement) surrounded by the myocardium. The prevalence of myocardial bridging detected by CTA and CA in ABS patients was compared with 401 controls without ABS who underwent both CTA and CA. RESULTS Myocardial bridging by CTA was observed in 32 ABS patients (76%): 23 with partial encasement and 9 with full encasement. All myocardial bridging was located in the mid segment of the left anterior descending coronary artery (LAD) with a mean length of 17 ± 9 mm. CA revealed myocardial bridging in 17 subjects (40%) (9 with partial encasement and 8 with full encasement by CTA). All subjects in which dynamic compression was observed by CA showed myocardial bridging by CTA, while none of the subjects with negative findings for myocardial bridging by CTA revealed dynamic compression by CA. Compared with controls, ABS patients showed a significant higher prevalence of myocardial bridging in the LAD either by CA (40% vs. 8%; p < 0.001) or by CTA (76% vs. 31%; p < 0.001). CONCLUSIONS Our study showed that myocardial bridging of the LAD is a frequent finding in ABS patients as revealed both by CA and, mostly, by CTA, suggesting a role of myocardial bridging as potential substrate in the pathogenesis of ABS.

PCI versus CABG for multivessel coronary disease in diabetics

Objectives: To explore the clinical performance of a strategy of revascularization by percutaneous coronary intervention (PCI) with drug‐eluting stent (DES) in diabetic patients with multivessel disease (MVD) compared with coronary artery bypass graft (CABG), when it is based on clinical judgment. Background: Diabetes mellitus (DM) is a major risk factor for poor outcome after PCI. However, PCI may result in better outcome if the choice of revascularization (PCI versus CABG) is based on the physician decision, rather than randomization. Limited experiences have compared revascularization by DES‐PCI versus CABG in DM patients with MVD. Methods: From August 2004 to August 2005, 220 consecutive DM patients with MVD underwent DES‐PCI (93) or CABG (127) at our Institution. The type of revascularization was dependent on patient and/or physician choice. Major adverse cardiac and cerebrovascular events (MACCE) included death, myocardial infarction, repeat coronary revascularization, and stroke. Results: Compared with PCI patients, CABG patients had higher prevalence of 3‐vessel disease (P < 0.001), significant LAD involvement (P < 0.001), presence of total occlusions (P = 0.04), collateral circulation (P < 0.001). At 2‐year follow‐up, MACCE were not different between CABG group and DES‐PCI group (OR 1.2; P = 0.6) and, only when the clinical judgment on the revascularization choice was excluded at propensity analysis, DES‐PCI increased the risk of 24‐month MACCE in total population (OR 1.8; P = 0.04). Conclusions: For patients with DM and MVD, a clinical judgment‐based revascularization by DES‐PCI is not associated with worse 2‐year outcome compared with CABG.

Valve Replacement for Severe Aortic Stenosis With Low Transvalvular Gradient and Left Ventricular Ejection Fraction Exceeding 0.50

BACKGROUND Severe aortic stenosis with a low transvalvular gradient and preserved left ventricular ejection fraction (LVEF) is often misdiagnosed, leading to undertreatment of such patients with no clear indication for surgical intervention. This study investigated the outcome of aortic valve replacement (AVR) in patients with severe aortic stenosis and a low transvalvular gradient despite normal LVEF. METHODS Between 1985 and 2008, we evaluated 73 patients who underwent AVR compared with 29 patients who did not. Overall, aortic valve area was 1.0 cm2 or smaller, LVEF was 0.50 or higher, and transvalvular gradient was 30 mm Hg or less. Multivariate and Cox analyses were used to compare these two groups according to AVR. RESULTS Compared with controls, AVR patients were younger and with higher body mass index. Coronary artery bypass grafting was performed simultaneously in 38 AVR patients (52%). At follow-up (median, 42 months; interquartile range, 23 to 75 months), survival was longer in AVR patients. By Cox analysis, AVR remained a major predictor of lower mortality (hazard ratio, 0.237; 95% confidence interval, 0.119 to 0.470; p<0.0001). CONCLUSIONS In patients with severe aortic stenosis and low transvalvular gradient despite a normal LVEF, AVR was associated with significant improvement in long-term survival and functional status and with a low operative mortality.

Haemodynamic effects of acute intravenous metoprolol in apical ballooning syndrome with dynamic left ventricular outflow tract obstruction.

Takotsubo syndrome, also called apical ballooning syndrome, is a clinical entity characterized by transient hypokinesis, akinesis, or dyskinesis of the left ventricular mid‐segments with or without apical involvement, and without obstructive coronary lesions. The contemporary presence of left ventricular outflow tract obstruction (LVOTO), systolic anterior motion of the anterior mitral leaflet, and acute mitral regurgitation might explain the worsening of the heart failure or the occurrence of cardiogenic shock in some patients with apical ballooning syndrome. The use of β‐blockers should improve the LVOTO gradient by reducing basal hypercontractility, increasing left ventricular filling and size, and reducing heart rate. However, clear evidence of the direct haemodynamic effects of β‐blockers is still lacking. We present a case of apical ballooning syndrome complicated by dynamic LVOTO, treated with metoprolol.

Impact of multivessel coronary artery disease on early ischemic injury, late clinical outcome, and remodeling in patients with acute myocardial infarction treated by primary coronary angioplasty.

ObjectiveThe mechanism through which multivessel coronary artery disease (MVD) adversely affects the outcome of patients with ST-elevation myocardial infarction (STEMI) is poorly characterized. We assessed whether the impact of MVD on outcome of STEMI patients is because of ischemic damage after primary percutaneous coronary intervention (PPCI) or to late ischemic events. MethodsFrom August 2005 to 2007, 288 STEMI patients treated by (bare metal) stent-PPCI were prospectively enrolled. The ischemic injury early after PPCI (evaluated by multiparametric approach) and the incidence of late adverse cardiovascular events were compared between the two groups. ResultsCompared with single vessel coronary artery disease, MVD patients (n=134) were older, with higher prevalence of diabetes, prior MI, anterior MI and higher collateral score. Myocardial perfusion as assessed by myocardial blush and ΣST-segment resolution was similar in the two groups as well as the infarct size and microvascular obstruction as assessed by Troponin I and by the delayed enhancement of cardiac magnetic resonance. At clinical (98% complete) and echocardiogaphic (94% complete) follow-up (median 32 months) MVD patients showed a higher incidence of re-MI (6.1 vs. 1.3%), and urgent revascularization (8.3 vs. 2.7%) and worse left ventricular remodeling than single vessel disease patients. At propensity adjusted analysis MVD was an independent predictor of re-MI (odds ratio: 5.7) and ventricular remodeling (odds ratio: 2.2). ConclusionThe impact of MVD on clinical outcome and remodeling of STEMI patients is not because of the extent of ischemic damage observed after PPCI, but to recurrent ischemic events during follow-up.

Design and Methodologies of the POSTconditioning during Coronary Angioplasty in Acute Myocardial Infarction (POST-AMI) Trial

Background: Reperfusion remains the definitive treatment for acute myocardial infarction (AMI), but restoring blood flow carries the potential to exacerbate the ischemia-related injury. Postconditioning might modify reperfusion-induced adverse events. Study Design: The POSTconditioning during Coronary Angioplasty in Acute Myocardial Infarction (POST-AMI) trial is a single-center, prospective, randomized study, with a planned inclusion of 78 patients with ST-elevation AMI. Patients will be randomly assigned to the postconditioning arm [primary angioplasty (PA) and stenting followed by brief episodes of ischemia-reperfusion early after recanalization] or non-postconditioning arm. All patients will be treated medically according to current international guidelines, including glycoprotein IIb/IIIa inhibitors before PA. The primary end point is to evaluate whether postconditioning, compared to plain PA, reduces infarct size estimated by cardiac magnetic resonance (CMR) at 30 ± 10 days after the AMI. Secondary end points are microvascular obstruction observed at CMR, ST-segment resolution, angiographic myocardial blush grade <2, non-sustained/sustained ventricular tachycardia in the 48 h following PA, left ventricular remodeling and function at follow-up CMR, and the reduction of major adverse cardiac events at 30 days and 6 months. Conclusion: The POST-AMI trial will evaluate the usefulness of postconditioning in limiting infarct size during the early and late phases after AMI.

Periprocedural Abciximab Administration in ST Elevation Myocardial Infarction Patients

Objectives: The impact of periprocedural (before primary percutaneous coronary angioplasty, PCI) abciximab administration on microvascular obstruction in patients with occluded infarct-related artery (IRA) is unknown. Methods: We studied 36 consecutive patients with first ST elevation myocardial infarction (STEMI) and occluded IRA treated with successful primary PCI within 12 h from symptom onset, who received intravenous abciximab immediately before PCI and 49 matched patients who did not receive abciximab as controls. All patients underwent delayed-enhanced magnetic resonance (DE-MR) 6 ± 2 days after PCI. Necrosis was judged as transmural when DE was extended to ≧75% of left ventricular (LV) segment thickness. Severe microvascular obstruction was identified as areas of late hypoenhancement surrounded by DE. Results: Time to treatment was comparable in the two groups (182 ± 60 vs. 188 ± 110 min, respectively). Transmurality and severe microvascular obstruction were present in 3.03 ± 2.8 versus 3.09 ± 2.9 (p = 0.9) and 1.05 ± 1.5 versus 1.06 ± 1.8 (p = 0.6) of LV segments, respectively, in the abciximab group versus controls. At multivariate analysis, severe microvascular obstruction was independently associated only with transmural necrosis (OR 1.5, p < 0.001) and age (OR 1.1, p = 0.02) but not with the use of abciximab. Conclusions: Severe microvascular obstruction after primary PCI of STEMI patients with occluded IRA is related to transmural necrosis but not to the use of abciximab.

Origin of recurrent syncope in patient with right ventricular outflow tract arrhythmias: evidence of autonomic modulation of the ectopic foci.

To the Editor. Right ventricular outflow tract premature contractions (RVOT-PVCs) represent a subtype of idiopathic ventricular outflow tract arrhythmias characterized by a left bundle branch block (LBBB) and inferior-axis morphology [1]. RVOT-PVCs are more frequent during daytime than at night, are transiently suppressed by effort or sinus tachycardia, and occur in the absence of structural heart diseases. It has been hypothesized that RVOTPVCs are caused by triggered activity, possibly by a c-AMP-mediated mechanism [1]. However, a neural basis in animal and in human models has been reported [2,3]. Patients with RVOT-PVCs may present recurrent syncope or near-syncope, but most of the time it is not possible to establish a correlation between symptoms and rhythm changes by outpatient electrocardiogram (ECG) monitoring. Indeed, patients with recurrent syncope and RVOT-PVCs may present sustained ventricular tachycardia and/or not sustained ventricular tachycardia as the cause of syncope. However, syncope may also have a neurocardiogenic etiology. We present a case of recurrent syncope in a patient with RVOT-PVCs, in whom a neurocardiogenic etiology of syncope was diagnosed. Moreover, we demonstrate how the autonomic activity plays a relevant role in the modulation of RVOT-PVCs.