Francesco Giraldi

Left Mitral Isthmus Ablation Associated with PV Isolation: Long-Term Results of a Prospective Randomized Study

Background: The deployment of an ablation line connecting the left inferior PV to the mitral annulus (mitral isthmus line [MIL]) enhances the efficacy of pulmonary vein disconnection (PVD) in preventing atrial fibrillation (AF) recurrences.

Isolated ultrafiltration in moderate congestive heart failure.

OBJECTIVES The aim of this study was to evaluate whether ultrafiltration is beneficial in patients with moderate congestive heart failure. BACKGROUND Ultrafiltration is beneficial in patients with severe congestive heart failure. METHODS We studied 36 patients in New York Heart Association functional classes II and III in stable clinical condition. Eighteen patients (group A) were randomly selected and underwent a single session of ultrafiltration (venovenous bypass, mean [+/- SEM] ultrafiltrate 1,880 +/- 174 ml, approximately 600 ml/h) and 18 (group B) served as control subjects. RESULTS Two patients in group A and three in group B did not complete the 6-month follow-up study. In group A, soon after ultrafiltration there were significant reductions in right atrial pressure (from 8 +/- 1 to 3.4 +/- 0.7 mm Hg, pulmonary wedge pressure (from 18 +/- 2.5 to 10 +/- 1.9 mm Hg) and cardiac index (from 2.8 +/- 0.2 to 2.3 +/- 0.2 liters/min). During the follow-up period, lung function improved, extravascular lung water (X-ray score) decreased and peak oxygen consumption (ml/min per kg) increased significantly from 15.5 +/- 1 (day -1) to 17.6 +/- 0.9 (day 4), to 17.8 +/- 0.9 (day 30), to 18.9 +/- 1 (day 90) and to 19.1 +/- 1 (day 180). Oxygen consumption at anaerobic threshold (ml/min per kg) also increased significantly from 11.6 +/- 0.8 (day -1) to 13 +/- 0.7 (day 4), to 13.7 +/- 0.5 (day 30), to 15.5 +/- 0.8 (day 90) and to 15.2 +/- 0.8 (day 180). These changes were associated with increased ventilation, tidal volume and dead space/tidal volume ratio at peak exercise. The improvement in exercise performance was associated with a decrease in norepinephrine at rest, a downward shift of norepinephrine kinetics at submaximal exercise and an increase in norepinephrine during orthostatic tilt. None of these changes were recorded in group B. CONCLUSIONS In patients with moderate congestive heart failure, ultrafiltration reduces the severity of the syndrome.

Interrelation of humoral factors, hemodynamics, and fluid and salt metabolism in congestive heart failure: Effects of extracorporeal ultrafiltration

PURPOSE We investigated the mechanisms involved in the regulation of salt and water metabolism in patients with congestive heart failure (CHF). Extracorporeal ultrafiltration was utilized as a nonpharmacologic method for withdrawal of body fluid. PATIENTS, METHODS, AND RESULTS In 32 consecutive patients with CHF (New York Heart Association functional class II to IV) and different degrees of water retention, 24-hour diuresis and natriuresis were inversely best correlated with the combination of circulating renin, aldosterone, norepinephrine, and renal perfusion pressure (RPP, mean aortic pressure minus mean right atrial pressure). Fluid withdrawal (600 to 5,000 mL) at a rate of 500 mL/h, until right atrial pressure decreased to 50% of baseline, caused variable humoral, circulatory, and diuretic effects that were mainly related to the extent of fluid retention. In fact, in 10 patients (Group 1) with overhydration refractory to drug therapy and with urinary output less than 1,000 mL/24 h (mean, 370 mL), soon after the procedure, plasma renin (-39%), aldosterone (-50%), and norepinephrine (-47%) were reduced and RPP was increased (+16%), and in the subsequent 24 hours, diuresis was increased by 493%; in 9 patients (Group 2) whose baseline urinary output exceeded 1,000 mL/24 h (mean, 1,785 mL), renin increased by 40%, norepinephrine, aldosterone, and RPP each decreased by 12%, and diuresis remained unchanged; in 13 patients (Group 3) with a daily urinary excretion as in Group 2 and without overhydration, RPP decreased (-7%), renin (+196%), aldosterone (+170%), and norepinephrine (+52%) increased, and diuresis decreased by 45%. There was an overall correlation (p < 0.0001) between the combination of changes in these circulatory and hormonal variables and changes in diuresis and natriuresis with ultrafiltration. CONCLUSIONS It appears that in CHF, (1) retention of sodium and water results from an interaction of hormonal and hemodynamic (primarily RPP) alterations that may exert a reciprocal positive feedback; (2) depending on the presence and severity of fluid retention, the response to withdrawal of body fluid may vary from neurohumoral activation and restriction of diuresis to neurohumoral depression and extreme potentiation of salt and water excretion; (3) refractory CHF requires the interruption of the humoral-hemodynamic vicious circle, and ultrafiltration is able to accomplish that.

Atrial pacing or ventricular backup–only pacing in implantable cardioverter-defibrillator patients

BACKGROUND The need for pacing support in typical ICD patients is unknown. OBJECTIVE This study sought to determine whether atrial pacing with ventricular backup pacing is equivalent to ventricular backup pacing only in implantable cardioverter-defibrillator (ICD) patients. METHODS We randomized 1,030 patients from 84 sites with indications for ICDs, with sinus rhythm, and without symptomatic bradycardia to atrial pacing with ventricular backup at 60 beats/min (518) or ventricular backup pacing at 40 beats/min (512). The primary end points were time to death, heart failure hospitalization (HFH), and heart failure-related urgent care (HFUC). RESULTS Follow-up was 2.4 ± 0.8 years when the trial was stopped for futility. There were 355 end point events (103 deaths, 252 HFH/HFUC) in 194 patients favoring ventricular backup pacing (event-free rate 77.7% vs. 80.3% for atrial pacing at 30 months; hazard ratio 1.14, upper confidence bound 1.59, prespecified noninferiority threshold 1.21), therefore equivalence between pacing arms was not demonstrated. Overall HFH/HFUC rates were slightly higher during atrial pacing (event-free rate 85.4% vs. 86.4% for ventricular backup pacing). Exploratory analyses revealed that the difference in HFH/HFUC rates was largely seen in patients with a PR interval ≥230 ms. There were no differences between groups for atrial fibrillation, ventricular tachycardia/ventricular fibrillation, quality of life, or echocardiographic measurements. Fewer patients in the atrial pacing group were reported to develop an indication for bradycardia pacing (3.7% vs. 7.3%, P = .0053). CONCLUSION Equivalence between atrial pacing and ventricular backup pacing only could not be demonstrated. CLINICAL TRIALS IDENTIFIER NCT00281099.

Percutaneous cardiopulmonary support for catheter ablation of unstable ventricular arrhythmias in high-risk patients.

Background and Purpose:In patients with severe cardiomyopathy, recurrent episodes of nontolerated ventricular tachycardia (VT) or electrical storm (ES) frequently cause acute heart failure and cardiac death; the suppression of the arrhythmia is therefore lifesaving, but feasibility of catheter ablation (CA) is precluded by the adverse hemodynamic conditions together with the characteristics of the arrhythmia that interdicts efficacious mapping. The use of the percutaneous cardiopulmonary support (CPS) for circulatory assistance may allow patient’s stabilization and enhance efficacy and safety of CA in this emergency setting.Patients and Methods:19 patients (19 males; mean age 61 ± 6 years; chronic ischemic cardiomyopathy, eleven patients; primary dilated cardiomyopathy, six patients; arrhythmogenic right ventricular dysplasia/ cardiomyopathy, two patients) with recurrent nontolerated VT episodes undergoing CPS-assisted CA were retrospectively evaluated. Twelve patients had acute hemodynamic failure refractory to inotropic agents and ventilatory assistance, seven patients had undergone a failing nonconventional CA procedure. 14 patients presented with ES, and in twelve the procedure was undertaken under emergency conditions within 24 h from admission. Patients were ventilated under general anesthesia and assisted by a multidisciplinary team. The CPS system consisted in a Medtronic Bio-Medicus centrifugal pump and in a Maxima Plus oxygenator, a 15-F arterial cannula, and a 17-F venous cannula.Results:Flows between 2 and 3 l/min were activated after induction of 56/62 forms of nontolerated VT, achieving hemodynamic stabilization in all patients. CA was mainly guided by conventional activation mapping and was effective in abolishing 45/56 supported VTs; in 10/19 patients all clinical VTs were suppressed by CA. Mean procedural time was 4 h and 20 min. Complete stabilization was achieved in 13 patients (68%) without VT recurrence during a 7-day in-hospital monitoring. A significant clinical improvement was observed in two patients (11%); one patient (5%) with persistent VT episodes acutely died after heart transplant. At a mean follow-up of 42 months (range 15–60 months), 5/18 patients (28%) were free from VT recurrence, 7/18 (39%) had a clear clinical improvement with reduced implantable cardioverter defibrillator interventions. 5/14 patients (36%) had ES recurrence; among them, three died because of acute heart failure. No serious CPS-related complications were observed.Conclusion:The CPS warrants acceptable hemodynamic stabilization and efficacious mapping in highrisk patients undergoing CA for unstable VT in the emergency setting. Safety and efficacy of this technique translate into significant clinical improvement in the majority of patients. Even if only relatively invasive, CPS should be reserved to patients with ES or intractable arrhythmia causing acute heart failure; moreover, the need for an experienced team of multidisciplinary operators implies that its use is restricted to selected high-competency institutions.ZusammenfassungHintergrund und Fragestellung:Bei Patienten mit schwerer Kardiomyopathie verursachen rezidivierende Episoden nicht tolerierter ventrikulärer Tachykardie (VT) oder eines elektrischen Sturms (ES) häufig akutes Herzversagen und plötzlichen Herztod; die Suppression der Arrhythmie ist daher lebensrettend, jedoch stehen der Durchführbarkeit der Katheterablation (KA) ungünstige hämodynamische Verhältnisse sowie die Charakteristika der Arrhythmie, die ein effizientes Mapping verhindert, entgegen. Der Einsatz des perkutanen kardiopulmonalen Supports (KPS) zur Kreislaufunterstützung kann zur Stabilisierung des Patienten beitragen und die Effizienz und Sicherheit der KA in diesem Notfallszenario erhöhen.Patienten und Methodik:19 Patienten (19 Männer; Durchschnittsalter 61 ± 6 Jahre; chronische ischämische Kardiomyopathie, elf Patienten; primäre dilatative Kardiomyopathie, sechs Patienten; arrhythmogene rechtsventrikuläre Dysplasie/Kardiomyopathie, zwei Patienten) mit rezidivierenden nicht tolerierten VT-Episoden, die einer KPS-unterstützten KA unterzogen wurden, wurden retrospektiv evaluiert. Zwölf Patienten hatten ein akutes, gegenüber inotropen Agenzien und assistierter Beatmung refraktäres hämodynamisches Versagen. Sieben Patienten hatten sich einem frustranen nichtkonventionellen KA-Verfahren unterzogen. 14 Patienten hatten ES, und bei zwölf wurde das Verfahren innerhalb von 24 h nach der Aufnahme unter Notfallbedingungen durchgeführt. Die Patienten wurden unter Vollnarkose beatmet und von einem multidisziplinären Team unterstützt. Das KPS-System bestand aus einer Medtronic-Bio-Medicus-Zentrifugalpumpe und einem Maxima-Plus-Oxygenator, einer arteriellen Kanüle (15 F) und einer venösen Kanüle (17 F).Ergebnisse:Nach der Induktion von 56/62 Formen nicht tolerierter VT wurden Flussraten zwischen 2 und 3 l/min eingestellt, so dass bei allen Patienten eine hämodynamische Stabilisierung erreicht wurde. Die KA wurde hauptsächlich durch konventionelles Aktivierungsmapping geführt, und sie war effizient bei der Beseitigung von 45/56 VT mit KPS; bei 10/19 Patienten wurden alle klinischen VT durch KA supprimiert. Die mittlere Eingriffszeit betrug 4 h und 20 min. Bei 13 Patienten (68%) wurde eine völlige Stabilisierung ohne rezidivierende VT während einer 7-tägigen stationären Überwachung erreicht. Bei zwei Patienten (11%) wurde eine erhebliche klinische Verbesserung beobachtet; ein Patient (5%) mit persistierenden VT-Episoden verstarb akut nach einer Herztransplantation. Nach einem mittleren Beobachtungszeitraum von 42 Monaten (Range 15–60 Monate) waren 5/18 Patienten (28%) in Bezug auf die VT rezidivfrei und 7/18 (39%) zeigten eine deutliche klinische Verbesserung mit weniger ICD-Interventionen (implantierbarer Kardioverter-Defibrillator). 5/14 Patienten (36%) hatten ES-Rezidive; davon starben drei aufgrund von akutem Herzversagen. Es wurden keine schweren, mit dem KPS im Zusammenhang stehenden Komplikationen beobachtet.Schlussfolgerung:Der KPS garantiert eine akzeptable hämodynamische Stabilisierung und effizientes Mapping bei Hochrisikopatienten, die sich notfallmäßig aufgrund einer instabilen VT einer KA unterziehen. Die Sicherheit und Effizienz dieser Technik führen bei der Mehrheit der Patienten zu einer erheblichen klinischen Verbesserung. Selbst wenn der KPS nur relativ invasiv ist, sollte er beschränkt sein auf Patienten mit ES oder hartnäckiger Arrhythmie, die akutes Herzversagen verursacht. Ferner impliziert die Notwendigkeit eines erfahrenen multidisziplinären Teams einen limitierten Einsatz in ausgewählten Einrichtungen mit hoher Fachkompetenz.

Long-term effectiveness of cardiac resynchronization therapy in heart failure patients with unfavorable cardiac veins anatomy comparison of surgical versus hemodynamic procedure.

OBJECTIVES This study sought to compare clinical, echocardiographic, and cardiopulmonary exercise testing response to cardiac resynchronization therapy (CRT) in patients with unfavorable anatomy of coronary sinus (CS) veins, randomized to transvenous versus surgical left ventricular (LV) lead implantation. BACKGROUND CRT efficacy depends on proper positioning of the LV lead over the posterolateral wall. A detailed pre-operative knowledge of CS anatomy might be of pivotal importance to accomplish a proper LV lead placement over this area. METHODS Study population included 40 patients (age 66 ± 4 years) with heart failure and indication to CRT, with unsuitable CS branches anatomy documented by pre-operative multislice computed cardiac tomography; 20 patients (Group 1) underwent surgical minithoracotomic LV lead implantation whereas 20 (Group 2) were implanted transvenously. New York Heart Association functional class, echocardiographic, and cardiopulmonary exercise testing data were assessed before and 1 year after CRT-system implant. RESULTS In all Group 1 patients, the LV leads were placed over the middle-basal segments of the posterolateral wall of the LV. This was not possible in Group 2 patients. One year after CRT, in Group 1, a significant improvement of New York Heart Association functional class, LV ejection fraction (from 28.8 ± 9.2% to 33.9 ± 7.2%, p < 0.01), LV end-systolic volume (from 165 ± 53 ml to 134 ± 48 ml, p < 0.001), and peak Vo(2)/kg (from 10.4 ± 4.5 ml/kg/min to 13.1 ± 3.1 ml/kg/min, p < 0.02) was observed. However, no improvement was observed in Group 2: LV ejection fraction varied from 27.4 ± 4.8% to 27.4 ± 5.7% (p = 0.9), LV end-systolic volume from 175 ± 46 ml to 166 ± 44 ml (p = 0.15), and peak Vo(2)/kg from 11.2 ± 3.2 ml/kg/min to 11.3 ± 3.4 ml/kg/min (p = 0.9). Changes after CRT between groups were highly significant. CONCLUSIONS In the setting of unfavorable CS branches of anatomy, CRT by a surgical minithoracotomic approach is preferable to transvenous lead implantation.

Usefulness of excitable gap and pattern of resetting in atrial flutter for determining reentry circuit location

Clinical and experimental data show that type I atrial flutter is due to a reentry mechanism with an excitable gap. To define the location of the reentry circuit of atrial flutter, width of excitable gap, poststimulation cycle and pattern of reset after premature stimulus were analyzed in 18 patients during atrial flutter at multiple atrial sites (high, lateral, posterior and septal right atrium, and coronary sinus). The pattern of reset was defined as flat or increasing whether the return cycle remained unchanged or prolonged with increasing prematurity. Shorter values of the excitable gap were found at the coronary sinus (33 +/- 8 ms) and high right atrium (30 +/- 10 ms) than at the posterior (43 +/- 9 ms) or septal right atrium (45 +/- 11 ms). Intermediate values (36 +/- 8 ms) were measured at the lateral right atrium. Poststimulation cycle, corrected for atrial flutter cycle length, was shorter in the posterior (6 +/- 7 ms) and septal right atrium (5 +/- 7 ms) than in the coronary sinus (35 +/- 9 ms), and the high (23 +/- 10 ms) and lateral right atrium (15 +/- 9 ms). A flat pattern of resetting occurred more frequently at the septal (18 of 18 patients) and posterior right atrium (15 of 18) than at the lateral (8 of 18) and high right atrium (2 of 17), and was never observed at the coronary sinus. Atrial flutter was successfully terminated by overdrive atrial pacing in 15 of 18 patients, and termination was more easily obtained from the septal and posterior right atrium.(ABSTRACT TRUNCATED AT 250 WORDS)

Imaging of cardiac venous system in patients with dilated cardiomyopathy by 64-slice computed tomography: Comparison between non-ischemic and ischemic etiology

It is unknown whether dilated cardiomyopathy (DCM) etiology influences cardiac veins (CVs) anatomy. By multidetector computed tomography (MDCT) we studied CVs of 93 patients with normal cardiac function (Group1) and of 99 DCM patients. In the latter we used a standard scanning coronary artery protocol (Group2, n=62) or a protocol specifically tailored to assess CVs in DCM (Group3, n=37). We also performed in all patients invasive coronary angiography. Group 1 had more CVs (83%) vs. DCM patients (72% and 76% in Groups 2 and 3 respectively, p<0.05). Group 2 had a higher percentage of CVs with insufficient imaging quality score (43 out of 224 veins, 19%) vs. Group 1 (6%, p<0.01) and Group 3 (11%, p<0.05) mainly due to low signal/noise ratio (32 out of 43 veins, 74%). Ischemic DCM patients had a lower CVs number (86/135, 64%) vs. both Group 1 patients and vs. non-ischemic DCM. Therefore MDCT is feasible for assessing CVs in DCM using scanning CVs tailored protocols. Ischemic DCM patients have a lower number of CVs compared to normal systolic function or non-ischemic DCM patients.

β-Thromboglobulin plasma levels in the first week after myocardial infarction: Influence of thrombolytic therapy

In vitro and in vivo studies have shown both an inhibition and an activation of platelets after thrombolysis in acute myocardial infarction. Plasma beta-thromboglobulin, a marker of platelet activity, was evaluated daily during the first week after myocardial infarction in 24 patients who received intravenous streptokinase (group 1) and 26 who did not (group 2). On admission, levels of beta-thromboglobulin, as compared to those in healthy subjects (35 +/- 9 IU/ml), were similarly augmented in group 1 (105 +/- 27 IU/ml) and in group 2 (115 +/- 30 IU/ml); 3 hours later, values averaged 191 +/- 58 IU/ml in group 1 (p < 0.001 vs baseline) and 95 +/- 28 IU/ml in group 2 (not significant vs baseline; p < 0.001 between the two groups). From the second to the seventh day, beta-thromboglobulin augmented in those patients in both groups with postinfarction angina. From day 5 to day 7, patients of group 1 without angina had lower beta-thromboglobulin levels than patients of group 2 who had no symptoms. The lowest levels of platelet activity were observed in group 1 reperfused patients. These data indicate that in myocardial infarction an early platelet activation takes place that is enhanced by thrombolytic treatment; recurrence of angina is associated with persistent activation; in the absence of recurrent angina, thrombolysis can limit late platelet activation.

Radiofrequency Catheter Ablation of Life-Threatening Ventricular Arrhythmias Caused by Left Ventricular Metastatic Infiltration

Metastases to the cardiac ventricles are rare and, unfortunately, often follow a rapidly fatal course.1,2 Occasionally, they cause symptomatic ventricular arrhythmias (VAs) for which limited therapeutic options exist, such as antiarrhythmic drugs, whereas the use of catheter ablation, to our knowledge, has never been reported to date. We present the case of a 27-year-old man with a metastatic tumor in the left ventricle and intractable malignant VAs. In February 2009, the patient had been diagnosed with a gluteal sarcoma and initially treated with combined chemotherapy (including anthracyclines) and radiation. Since December 2009, a mild reduction in left ventricular ejection fraction (45%) was detected, and since January 2010, frequent monomorphic premature ventricular contractions (PVCs) and nonsustained ventricular tachycardias (VTs) were documented. Treatment with amiodarone proved helpful, and no life-threatening VAs could be induced on standard electrophysiological study.3 Since April 2010, however, the patient suffered from multiple drug-refractory episodes of sustained VT and ventricular fibrillation, requiring several direct current shocks (Figure 1). His left ventricular ejection fraction had remained stable. Electrical storm resulted in immediate hemodynamic instability and dramatically affected his quality of life. The patient was referred to our institution, where multiple antiarrhythmic drug combinations were tested, both orally and intravenously, allowing a relative stabilization of cardiac rhythm. Cardiac MRI showed a T2-hyperintense, weakly gadolinium-enhanced area at the basis of the anterior papillary muscle, compatible with metastatic infiltration (Figure 2, online-only Data Supplement Movie 1). An oncology consultation hypothesized a life expectancy of <6 months. After about 2 weeks, the recurrence of multiple episodes of VT and ventricular fibrillation required intensive care treatment with deep sedation and assisted ventilation, but still VAs could not be controlled. Thus, a repeat electrophysiological evaluation and radiofrequency …