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The use of cardiac magnetic resonance (cMR) to assess remodeling and tissue characterization in primitive and secondary cardiomyopathies has progressively increased, and it carries important prognostic informations. The aim of this study was to assess the overall clinical value of cMR before implantable cardioverter defibrillator (ICD). All patients referred to our center for an ICD implantation and submitted to cMR (n = 134) were analyzed. All the cMR diagnostic findings and following clinical events were reviewed to assess clinical relevance in patients care. The use of cMR before ICD implantation has progressively increased during the decade studied (13% to 53%, p <0.001). Subjects who underwent cMR were younger, more often female, with lower NYHA class and higher ejection fraction (p <0.05 for all). Unexpected diagnostic findings were observed in 34 patients (25%), resulting in an immediate therapeutic strategy modification in 13%. A pattern of fibrosis leading to a change in the disease's etiology and thrombus detection were the most frequent cMR findings, followed by anatomical incidental findings. Any grade of fibrosis carried a higher annual incidence of combined death or ventricular arrhythmias (9.92% vs 1.83%, p = 0.02). Annual event rate was related to the extent of scarring. In conclusion, we observed a progressively increase of cMR utilization before ICD implantation during the last decade. This practice has yielded a significant increase of new diagnostic findings, carrying unique prognostic information linked to tissue characterization., (Copyright © 2018. Published by Elsevier Inc.)

Objective: The aim of the study was to compare the two approaches to chronic right ventricular pacing currently adopted in clinical practice: right ventricular apical (RVA) and non-RVA pacing., Background: Chronic RVA pacing is associated with an increased risk of atrial fibrillation, morbidity, and even mortality. Non-RVA pacing may yield more physiologic ventricular activation and provide potential long-term benefits and has recently been adopted as standard procedure at many implanting centers., Methods: The Right Pace study was a multicenter, prospective, single-blind, nonrandomized trial involving 437 patients indicated for dual-chamber pacemaker implantation with a high percentage of RV pacing., Results: RV lead-tip target location was the apex or the interventricular septum. RVA (274) and non-RVA patients (163) did not differ in baseline characteristics. During a median follow-up of 19 months (25th-75th percentiles, 13-25), 17 patients died. The rates of the primary outcome of death due to any cause or hospitalization for heart failure were comparable between the groups (log-rank test, p = 0.609), as were the rates of the composite of death due to any cause, hospitalization for heart failure, or an increase in left ventricular end-systolic volume ≥ 15% as compared with the baseline evaluation (secondary outcome, p = 0.703). After central adjudication of X-rays, comparison between adjudicated RVA (239 patients) and non-RVA (170 patients) confirmed the absence of difference in the rates of primary ( p = 0.402) and secondary ( p = 0.941) outcome., Conclusions: In patients with indications for dual-chamber pacemaker who require a high percentage of ventricular stimulation, RVA or non-RVA pacing resulted in comparable outcomes. This study is registered with ClinicalTrials.gov (identifier: NCT01647490).

Background: Multidetector coronary computed tomography angiography (CCTA) is increasingly used for noninvasive imaging of the coronary arteries. Radiation exposure, however, is a potential limitation to a more extensive use of this imaging modality. We aimed to demonstrate that a professional teamwork approach, including a cardiologist and a radiologist in performing CCTA, may allow to obtain best quality exams with very low radiation doses., Methods: A total of 998 consecutive patients underwent CCTA in accordance with the most recent guidelines. The following procedures were undertaken to reduce the radiation dose: (a) preliminary cardiological evaluation to check for CCTA eligibility; (b) optimized heart rate control with beta-blockers and/or ivabradine; and (c) the use of nonstandardized computed tomography protocols and algorithms for dose reduction., Results: All the patients underwent a preliminary cardiological evaluation; 89% of them were pretreated with oral or intravenous beta-blockers and/or ivabradine; 806 patients (81%) were scanned by means of prospective gating, which allowed a radiation dose exposure of 161 ± 68.64 mGy; 192 patients (19%) underwent a retrospective gating protocol, with a radiation dose exposure of 1135.15 ± 485.87 mGy. In 13 patients (1%) CCTA was uninterpretable because of artifacts. Exam quality was not affected by the use of low-dose computed tomography scanning. Coronary calcium score and/or left ventricular functional analysis were never performed., Conclusions: The preliminary selection and preparation of patients and optimized scanner utilization allow a substantial reduction in radiation dose for most of the patients submitted to CCTA without affecting image quality. In our experience, a team approach was necessary to allow a "low-dose learning curve" and a progressive reduction in radiation doses administered to patients by means of the prospective gating protocol.

Background: Left ventricular (LV) twist represents a main aspect of ejection. It is defined as the difference between the apical and basal rotation and can be assessed by speckle tracking echocardiography (STE). Twist may be underestimated when assessed by two-dimensional-echocardiography due to the difficulty of identifying the real apex. Aim of this study was to evaluate the LV twist by means of three-dimensional (3D)-STE and verify if the inclusion of the apex can modify the assessment of the global twist., Methods: LV volume acquisition with a fully sampled matrix array transducer was performed in 30 healthy subjects and 79 patients with cardiomyopathy secondary to different etiologies. Thirty-nine patients had a LV ejection fraction (EF) ≥50% (Group A), 16 showed an EF between 40 and 50% (Group B), and 24 patients had an EF ≤40%(Group C). LV rotation was assessed by 3D-STE at basal, medium, apical, and apical-cap levels. Twist was computed considering the apex either at the apical level (Twist(Api) ) or at the apical-cap level (Twist(AC) )., Results: LV rotation resulted to be progressively higher from base to apical-cap (P < 0.0001) with a significant difference between the apex and the apical-cap level (6.20 ± 3.90° vs. 10.23 ± 7.52°; P < 0.001). Such a difference was constantly found in all Groups (P < 0.01 for Group A, P < 0.05 for Group B and C). Twist(Api) was also significantly lower than Twist(AC) both in the overall population (6.2 ± 3.89° vs. 10.23 ± 7.51°; P < 0.001) and in the different subgroups (, Controls: 9.61 ± 3.39° vs. 13.75 ± 6.51°; Group A: 10.49 ± 4.77° vs. 16.37 ± 8.49°; Group B: 6.67 ± 3.44° vs. 9.14 ± 5.55°; Group C: 33 ± 2.62° vs. 5.26 ± 3.74°; P < 0.05 for all the comparisons)., Conclusions: Identification and inclusion of apical-cap is relevant for twist assessment and can be carried out efficiently by 3D-STE. The inclusion of the true apex in the calculation significantly affects the analysis of twist both in normal individuals and patients with different myocardial diseases., (© 2012, Wiley Periodicals, Inc.)

Aims: Three-dimensional (3D)-echocardiography speckle imaging allows the evaluation of frame-by-frame strain and volume changes simultaneously. The aim of the present investigation was to describe the strain-volume combined assessment in different patterns of cardiac remodelling., Methods and Results: Fifty patients received a 3D acquisition. Patients were classified as follows: healthy subjects (CNT), previous AMI, and normal ejection fraction (EF; group A); ischaemic cardiomyopathy with reduced EF (group B); hypertrophic/infiltrative cardiomyopathy (group C). Values of 3D strain were plotted vs. volume for each frame to build a strain-volume curve for each case. Peak of radial, longitudinal, and circumferential systolic strain (Rεp, Lεp, and Cεp, respectively), slopes of the curves (RεSl, LεSl, CεSl), and strain to end-diastolic volume (EDV) ratio (Rε/V, Lε/V, Cε/V) were computed for the analysis. Strain-volume curves of the CNT group were steep and clustered, whereas, due to progressive dilatation and reduction of strains, progressive flattening could be demonstrated in groups A and B. Quantitative data supported visual assessment with progressive lower slopes (P< 0.05 for RεSl, CεSl, P= 0.06 for LεSl) and significantly lower ratios (P< 0.01 for Rε/V, Lε/V, and Cε/V). Group C showed an opposite behaviour with slopes and ratios close to those of normal subjects. Correlation coefficients between EDV and slopes of the curves were significant for all the directions of strain (CεSl: r = 0.891; RєSl: r = 0.704; LєSl: r = 0.833; P< 0.0001 for all)., Conclusion: We measured left ventricular volumes and strain by 3D-echo and obtained strain-volume curve to evaluate their behaviour in remodelling. A distinctive and progressive pattern consistent with pathophysiology was observed. The analysis here shown could represent a new non-invasive method to assess myocardial mechanics and its relationship with volumes.

125I-labeled atrial natriuretic peptide (ANP) was bolus injected into seven healthy human male subjects on an unrestricted diet (sodium intake ranging from 80 to 300 mmol/day). A high-performance liquid chromatographic procedure was used to purify the labeled hormone and the principal labeled metabolites in venous plasma samples collected up to 50 min after injection. The main ANP kinetic parameters were derived from the disappearance curves of the 125I-ANP, which were satisfactorily fitted by a biexponential function in all subjects. Newly produced ANP initially distributes in a large space (plasma-equivalent volume is 12.1 +/- 3.6 l/m2 body surface); the hormone rapidly leaves this sampling space through both degradation and distribution in peripheral spaces, as indicated by the single-pass mean transit time through the sampling space (3.9 +/- 1.2 min). The mean residence time in the body (22.7 +/- 23.1 min) and the plasma-equivalent total distribution volume (30.9 +/- 12.0 l/m2) indicate that ANP is also widely distributed outside the initial space. Metabolic clearance rate (MCR) values were distributed across a wide range (from 740 to 2,581 ml.min-1 x m-2) and were shown to correlate strongly with the daily urinary excretion of sodium. These results indicate that: 1) newly produced ANP is rapidly distributed and degraded, 2) the body pool of the hormone can be considered as a combination of two exchanging spaces, 3) circulating ANP is < or = 1/15 of the body pool, and 4) MCR of ANP is closely related to sodium intake, at least in normal subjects on a free sodium intake diet.

The association of ventricular arrhythmias and myocardial dysfunction could be considered an early step toward cardiomyopathy; therefore, we studied 28 patients in NYHA class I and II, characterized by complex ventricular arrhythmias (VA) on 24-h Holter monitoring and volumetric and/or contractile abnormalities on a standard two-dimensional echocardiogram (2-D echo). All patients underwent radioisotopic angiography, 20 patients complete hemodynamic study, and 15 patients endomyocardial biopsy. Ambulatory ECG monitoring showed the presence of frequent premature ventricular contractions in 14 patients (50%) and episodes of ventricular tachycardia in 16 patients (57%). 2-D echo showed mono- or biventricular enlargement and dyssynergies in 25 patients (89%) (left ventricle in 6, right ventricle in 11, both in 8). Two patients showed only left ventricle enlargement and one patient isolated left ventricular dyssynergies. Radioisotopic angiography showed mono- or biventricular ejection fraction reduction in 24 patients (85%) and regional dyssynergies in 24 patients (85%) in accordance with 2-D echo. Hemodynamic study showed in all patients normal coronary arteries, and right and left angiography confirmed enlargement and/or regional dyssynergies. Endomyocardial biopsy was abnormal in 11 of 15 patients: various degrees of hypertrophy, parcellar fibrosis, and adipogenic infiltration were found. Our preliminary data suggest that the simultaneous occurrence of ventricular arrhythmias and ventricular dyssynergies and/or enlargement in patients without apparent clinical heart disease may represent an early stage of dilated cardiomyopathy.

The study investigates the response of atrial natriuretic peptide (ANP) to different cardiac pacing modes in comparison with hemodynamic changes. Ten patients underwent Swan-Ganz catheterization during pacemaker implant. Atrioventricular and ventricular pacing were performed consecutively at three pacing rate levels (80, 100, and 110 ppm). Blood samples were taken from the pulmonary artery for ANP determination, both basally and at the end of each pacing period. Concomitantly, mean pulmonary capillary wedge pressure (PCWP) and mean pulmonary artery pressure (PAP) were measured. Cardiac output (CO) was determined by thermodilution both basally and during the 110 ppm steps. During atrioventricular pacing, whereas no significant changes were observed for ANP, PCWP and PAP, CO increased significantly (P less than 0.0005). At the beginning of ventricular pacing hemodynamic parameters and ANP levels were comparable with those of baseline conditions. During subsequent ventricular pacing PCWP and ANP increased significantly at the 110 ppm rate step (P less than 0.05). PAP did not change significantly, whereas CO decreased in all cases (P less than 0.01). A positive correlation was observed between ANP and PCWP during ventricular (P less than 0.001), but not atrioventricular pacing. The results, while confirming the hemodynamic advantages of atrioventricular pacing, point to a major stimulation of ANP secretion during ventricular pacing. This fact, together with the observed drop in CO and the correlation between ANP and PCWP, suggest that the increase of ANP in ventricular pacing may be the expression of a compensatory mechanism to the hemodynamic disadvantages of atrioventricular asynchrony.

The role of 24 hour Holter monitoring in the screening of patients complaining of palpitations is reviewed. The term "palpitations", although not always unequivocally used, implies the presence of an arrhythmia. The clinical-instrumental correlation of an intermittent symptom is made possible by continuous electrocardiographic monitoring. Answers to be expected from a 24 hour Holter monitoring in order to achieve an early characterization of the arrhythmia are related to: site of origin, incidence, circadian distribution, prognostic stratification, events aggregation, presence of other asymptomatic abnormalities (rhythm, ST-T).

The clinical recognition of perioperative myocardial necrosis represents one of the clue factors in the management of cardiac surgical patients (pts). This study was performed to determine whether there is any relationship between reperfusion ventricular fibrillation and/or ST-segment elevation and postoperative enzymatic release. Serum enzyme levels and ECG were monitored during and after cardiac operations in 23 pts (15 for valvular replacement and 8 for aortocoronary bypass graft). After aortic unclamping only 6 pts showed stable rhythm. Of the 17 pts who developed ventricular fibrillation 10 showed ST-segment elevation (83% of the 12 pts with ST-segment elevation). Although no significant difference was observed, pts with ST-segment elevation showed higher average enzyme (CK, CKMB) levels. Pts who had valvular replacement showed significantly higher serum CK and CKMB levels. Of the 4 pts who showed a second enzymatic peak, one died and another one presented complex ventricular arrhythmias. No correlation was observed between electrocardiographic data and post-operative enzymatic release. New theories concerning oxygen free radical generation during and after cardiopulmonary by-pass, with the related therapeutic perspectives, are discussed.