Electrocardiographic voltage criteria in patients with hypertrophic cardiomyopathy.

BACKGROUND: Several ECG voltage criteria have been proposed for the diagnosis of left ventricular hypertrophy (LVH). Notably, ECG criteria have been historically validated in concentric LVH but not in hypertrophic cardiomyopathy (HCM), wherein the hypertrophy pattern is typically asymmetric. OBJECTIVES: The aim of our study was to evaluate the performance of ECG voltage criteria for LVH diagnosis in the HCM population. MATERIAL AND METHODS: The electrocardiograms of 92 HCM patients and 41 sex- and age-matched controls were evaluated with the most frequently used ECG voltage criteria for LVH diagnosis. Cardiac magnetic resonance (MRI) was performed in HCM and controls in order to quantify LVH and its distribution. RESULTS: In the HCM population, the maximal diagnostic accuracy was achieved by Amplitude total and Amplitude total product criteria (58% for both), while the Cornell Voltage best performed in septal HCM (62%), the Sokolov in aVL and Gubner criteria in apical HCM (79% for both) and the Cornell Voltage and Product in anterior HCM (86% for both). All the ECG voltage criteria showed a poor correlation with left ventricular mass and maximal thickness measured by cardiac MRI. CONCLUSIONS: In our study, only a few ECG voltage criteria used for the detection of LVH in clinical practice showed an acceptable performance in the HCM population. Further studies are needed to clarify the role of ECG for LVH detection in HCM patients.

Prognostic Value of Magnetic Resonance Phenotype in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy.

BACKGROUND: Cardiac magnetic resonance (CMR) is widely used to assess tissue and functional abnormalities in arrhythmogenic right ventricular cardiomyopathy (ARVC). Recently, a ARVC risk score was proposed to predict the 5-year risk of malignant ventricular arrhythmias in patients with ARVC. However, CMR features such as fibrosis, fat infiltration, and left ventricular (LV) involvement were not considered. OBJECTIVES: The authors sought to evaluate the prognostic role of CMR phenotype in patients with definite ARVC and to evaluate the effectiveness of the novel 5-year ARVC risk score to predict cardiac events in different CMR presentations. METHODS: A total of 140 patients with definite ARVC were enrolled (mean age 42 ± 17 years, 97 males) in this multicenter prospective registry. As per study design, CMR was performed in all the patients at enrollment. The novel 5-year ARVC risk score was retrospectively calculated using the patient's characteristics at the time of enrollment. During a median follow-up of 5 years (2 to 8 years), the combined endpoint of sudden cardiac death, appropriate implantable cardioverter-defibrillator intervention, and aborted cardiac arrest was considered. RESULTS: CMR was completely negative in 14 patients (10%), isolated right ventricular (RV) involvement was found in 58 (41%), biventricular in 52 (37%), and LV dominant in 16 (12%). During the follow-up, 48 patients (34%) had major events, but none occurred in patients with negative CMR. At Kaplan-Meier analysis, patients with LV involvement (LV dominant and biventricular) had a worse prognosis than those with lone RV (p < 0.0001). At multivariate analysis, the LV involvement, a LV-dominant phenotype, and the 5-year ARVC risk score were independent predictors of major events. The estimated 5-year risk was able to predict the observed risk in patients with lone RV but underestimated the risk in those with LV involvement. CONCLUSIONS: Different CMR presentations of ARVC are associated with different prognoses. The 5-year ARVC risk score is valid for the estimation of risk in patients with lone-RV presentation but underestimated the risk when LV is involved.

Sacubitril/valsartan effect on left ventricular remodeling: the case of a super-responder.

Sacubitril/valsartan has been shown to improve clinical outcomes in patients with heart failure and reduced ejection fraction (HFrEF), but its effects on left ventricular (LV) systolic function and reverse remodeling parameters remain to be established. We hereby describe the case of a 41 year old man with HFrEF and severe reduction of left ventricular ejection fraction (LVEF). The patient was first treated with triple HF therapy (beta-blocker, angiotensin converting enzyme inhibitor and mineralocorticoid antagonist), but after three months he was still symptomatic and with an LVEF firmly low. In consideration of poor response to therapy, we switched angiotensin converting enzyme inhibitor to sacubitril/valsartan to the maximum tolerated dose (49/51 mg bid) with a marked improvement in LV systolic function and reduction in LV volumes at follow-up. In light of the almost normalized LVEF the patient was also removed from the list for the implantation of a cardiac resynchronization therapy defibrillator. In conclusion, our case showed a strong beneficial effect of sacubitril/valsartan on reverse remodeling and LVEF beyond the benefits of concomitant optimal medical therapy. This result is particular noteworthy because it was obtained although the patient wasn't able to reach the full dose of the drug. Physicians should always consider this drug effect when more demanding therapeutic strategies are needed for their HF patients.

Reference values of left heart echocardiographic dimensions and mass in male peri-pubertal athletes.

Background Several articles have proposed reference values in healthy paediatric subjects, but none of them has evaluated a large population of healthy trained adolescents. Design The study purpose was to establish normal echocardiographic measurements of left heart (aortic root, left atrium and left ventricular dimensions and mass) in relation to age, weight, height, body mass index, body surface area and training hours in this specific population. Methods We retrospectively evaluated 2151 consecutive, healthy, peri-pubertal athletes (100% male, mean age 12.4 ± 1.4 years, range 8-18) referred to a single centre for pre-participation screening. All participants were young soccer athletes who trained for a mean of 7.2 ± 1.1 h per week. Results Left ventricular internal diameters, wall thickness, left ventricular mass, aortic root and left atrium diameters were significantly correlated to age, body surface area, height and weight ( p < 0.01). Age, height, weight and body surface area were found associated with chamber size, while body mass index and training hours were not. Inclusion of both age and body size parameters in the statistical models resulted in improved overall explained variance for diameters and left ventricular mass. Conclusion Equations, mean values and percentile charts for the different age groups may be useful as reference data in efficiently assessing left ventricular parameters in young athletes.

Patients with left bundle branch block and left axis deviation show a specific left ventricular asynchrony pattern: Implications for left ventricular lead placement during CRT implantation.

BACKGROUND: Left bundle branch block (LBBB) and left axis deviation (LAD) patients may have poor response to resynchronization therapy (CRT). We sought to assess if LBBB and LAD patients show a specific pattern of mechanical asynchrony. METHODS: CRT candidates with non-ischemic cardiomyopathy and LBBB were categorized as having normal QRS axis (within -30° and +90°) or LAD (within -30° and -90°). Patients underwent tissue Doppler imaging (TDI) to measure time interval between onset of QRS complex and peak systolic velocity in ejection period (Q-peak) at basal segments of septal, inferior, lateral and anterior walls, as expression of local timing of mechanical activation. RESULTS: Thirty patients (mean age 70.6years; 19 males) were included. Mean left ventricular ejection fraction was 0.28±0.06. Mean QRS duration was 172.5±13.9ms. Fifteen patients showed LBBB with LAD (QRS duration 173±14; EF 0.27±0.06). The other 15 patients had LBBB with a normal QRS axis (QRS duration 172±14; EF 0.29±0.05). Among patients with LAD, Q-peak interval was significantly longer at the anterior wall in comparison to each other walls (septal 201±46ms, inferior 242±58ms, lateral 267±45ms, anterior 302±50ms; p<0.0001). Conversely, in patients without LAD Q-peak interval was longer at lateral wall, when compared to each other (septal 228±65ms, inferior 250±64ms, lateral 328±98ms, anterior 291±86ms; p<0.0001). CONCLUSIONS: Patients with heart failure, presenting LBBB and LAD, show a specific pattern of ventricular asynchrony, with latest activation at anterior wall. This finding could affect target vessel selection during CRT procedures in these patients.

Acute echocardiographic optimization of multiple stimulation configurations of cardiac resynchronization therapy through quadripolar left ventricular pacing: a tailored approach.

BACKGROUND: Cardiac resynchronization therapy (CRT) is ineffective in approximately 30% of recipients, in part due to sub-optimal left ventricular (LV) pacing location. The Quartet LV lead, with 2 additional electrodes proximal to conventional bipolar lead electrodes, enables 10 different pacing configurations at four independent LV locations. In a CRT patient cohort, we sought to evaluate the spectrum of echocardiographic and electrocardiographic response over these 10 configurations, to select the optimal one in each patient. Moreover, we sought to evaluate the 6-months clinical and echocardiographic response to a "tailored approach" in which the optimal LV pacing configuration for CRT was determined by echocardiographic measures, QRSd and pacing capture thresholds. METHODS: Twenty-two consecutive CRT indicated patients were implanted with a quadripolar CRT system (St. Jude Medical). Optimal LV pacing configuration was determined by echocardiographic measures, including velocity time integral (VTI), myocardial performance index (MPI) and mitral regurgitation (MR), and an electrocardiographic measure (QRS duration) during pacing from each of the configurations at pre-discharge. The optimal LV pacing vector was chosen for every patient. Clinical and echocardiographic assessment was repeated after 6 months. RESULTS: Various configurations provided different VTI, MPI, MR and QRSd values. Conventional bipolar vectors (ie, D1-M2, D1-RVc, M2-RVc) were rarely associated with the best echocardiographic improvements and provided significantly worse VTI, MR, MPI, and QRSd values than the best configuration for every patient (P = .005, P = .05 and P = .03 for VTI; P = .01, P = .005 and P = .001 for MPI; P = .003, P = .01 and P = .005 for MR, P > .5, P = .01 and P = .05 for QRSd) Conversely, "unconventional" proximal configurations (ie, making use of P4 and M3 electrodes) were generally characterized by higher acute VTI, MR and MPI improvements. CRT devices were reprogrammed with an "unconventional" LV pacing configuration in 50% of patients. A significant improvement in New York Heart Association class (81%), LV ejection fraction (76%), end-diastolic and end-systolic volumes was observed after 6 months (P = .02, P < .001, P = .02 and P = .003, respectively). CONCLUSIONS: In this study, conventional bipolar vectors of quadripolar-CRT were rarely associated with the best echocardiographic improvements. Quadripolar CRT utilizing optimal LV pacing configuration was associated with a significant improvement in New York Heart Association class and LV ejection fraction after 6 months.

Cardiac magnetic resonance detection of left ventricular thrombus in acute myocardial infarction.

INTRODUCTION: Left ventricular thrombosis (LVT) is a possible complication of acute myocardial infarction. Aim of our study was to evaluate incidence and clinical characteristics of patients with LVT after ST elevation myocardial infarction (STEMI) using contrast- enhanced magnetic resonance (CMR). METHODS AND RESULTS: In a prospective cohort of 36 consecutive patients with STEMI acutely reperfused with primary percutaneous coronary intervention, CMR was performed within one week. LVT was found in 7 patients (19%), and was located in left ventricle apex or adherent to antero-septum. Compared to the rest of population patients with LVT have lower ejection fraction (38 ± 7% versus 51 ± 6%, P = 0.009), larger left ventricle end systolic volume (95.8 ± 19 ml versus 68.9 ± 19 ml, P = 0.02), higher time to reperfusion (9.3 ± 7.2 versus 5 ± 3.6, P = 0.03) and left anterior descending artery was constantly involved (100% versus 41 %, P = 0.06). In 5 cases the LVT was also detected by echocardiography, however, in 2 cases it was missed. CONCLUSIONS: The incidence of LVT after STEMI is not negligible and was accurately detected by CMR. Localization of myocardial infarction, time to reperfusion, ejection fraction and left ventricle end systolic volume are the most important predictors of left ventricle thrombus formation.

Positioning of left ventricular pacing lead guided by intracardiac echocardiography with vector velocity imaging during cardiac resynchronization therapy procedure.

INTRODUCTION: Intraoperative modality for "real-time" left ventricular (LV) dyssynchrony quantification and optimal resynchronization is not established. This study determined the feasibility, safety, and efficacy of intracardiac echocardiography (ICE), coupled with vector velocity imaging (VVI), to evaluate LV dyssynchrony and to guide LV lead placement at the time of cardiac resynchronization therapy (CRT) implant. METHODS: One hundred and four consecutive heart failure patients undergoing ICE-guided (Group 1, N = 50) or conventional (Group 2, N = 54) CRT implant were included in the study. For Group 1 patients, LV dyssynchrony and resynchronization were evaluated by VVI including visual algorithms and the maximum differences in time-to-peak (MD-TTP) radial strain. Based on the findings, the final LV lead site was determined and optimal resynchronization was achieved. CRT responders were defined using standard criteria 6 months after implantation. RESULTS: Both groups underwent CRT implant with no complications. In Group 1, intraprocedural optimal resynchronization by VVI including visual algorithms and MD-TTP was a predictor discriminating CRT response with a sensitivity of 95% and specificity of 89%. Use of ICE/VVI increased number of and predicted CRT responders (82% in Group 1 vs 63% in Group 2; OR = 2.68, 95% CI 1.08-6.65, P = 0.03). CONCLUSION: ICE can be safely performed during CRT implantation. "Real-time" VVI appears to be helpful in determining the final LV lead position and pacing mode that allow better intraprocedural resynchronization. VVI-optimized acute resynchronization predicts CRT response and this approach is associated with higher number of CRT responders.

The new electroanatomical Carto3 mapping system: three-dimensional right ventricular fast anatomical map resolution in comparison to magnetic resonance image.

Three-dimensional mapping systems are required in some electrophysiological procedures in order to allow nonfluoroscopic catheter navigation, reconstruction of electrophysiological mechanisms, particularly of complex arrhythmias, and to facilitate catheter ablation. Accuracy in three-dimensional reconstructions of cardiac chambers is crucial to increase the effectiveness and safety of electrophysiological procedures. We report on the feasibility of the anatomical reconstruction of the right ventricular chamber by means of the new Carto3 system. The three-dimensional anatomical reconstruction of the right ventricle was compared to the magnetic resonance image of the same chamber.

Effects of abciximab and preprocedural glycemic control in diabetic patients undergoing elective coronary stenting.

BACKGROUND: In diabetic patients, the combination of abciximab with stenting has been demonstrated to be the standard of care to reduce target vessel revascularization (TVR) and mortality. Moreover, a preprocedural hyperglycemia has been associated with a higher rate of TVR after an elective stent implantation. We sought to evaluate the effects of abciximab and/or preprocedural glycemic control on 30 and 180 days of TVR and on 1-year major adverse cardiac events (MACE-cardiac mortality, TVR, and myocardial infarction) in diabetic patients undergoing elective coronary stenting. METHODS: From January 2002 through May 2003, diabetic patients undergoing elective stenting of de novo coronary artery lesions were randomized to abciximab or placebo infusion. Preprocedural hyperglycemia was defined as fasting plasma glucose >or=126 mg/dL (7.0 mmol/L) immediately before the procedure. RESULTS: A total of 122 consecutive patients with diabetes (62.4 +/- 10.2 years, 80 men) were enrolled in the study. Sixty-nine (56.5%) were randomly assigned to receive abciximab (34 with and 35 without preprocedural hyperglycemia) and 53 (43.5%) to placebo (23 with and 30 without hyperglycemia). Target vessel revascularization was significantly lower in diabetic patients who received abciximab at 30 days (2.9% and 2.8% vs 8.7% and 6.6% in nonabciximab group with or without hyperglycemia, respectively, P < .01) but not at 6 months (31.4% and 26.5% vs 30% and 28.7%, P = NS). Conversely, the cumulative incidence of MACE was significantly higher among diabetic patients with preprocedural hyperglycemia (64.7% and 65.2%) versus diabetic patients with preprocedural glycemic control (37.1% and 40%), treated with or without abciximab, respectively (P < .05). CONCLUSIONS: A preprocedural hyperglycemia is associated with a higher rate of MACE, regardless of the use of abciximab, in diabetic patients undergoing elective coronary stenting.