Giorgio Arpesella

Cox/Maze III operation versus radiofrequency ablation for the surgical treatment of atrial fibrillation: a comparative study

BACKGROUND The purpose of this study was to evaluate the efficacy of radiofrequency (RF) ablation in the treatment of atrial fibrillation, by comparatively analyzing the outcomes of the patients who underwent RF ablation with those of patients who underwent Cox/Maze III surgery. METHODS Between April 1995 and June 2002, 70 patients underwent surgery for atrial fibrillation and open-heart surgery at the Department of Cardiovascular Surgery of the University of Bologna: 30 patients underwent the surgical Cox/Maze III procedure (group 1), and 40 patients underwent the RF ablation according to the Maze III configuration at least on the left atrium (group 2). There were 14 males and 56 females, with a mean age of 61.5 +/- 12.5 years (range 22 to 80 years old). RESULTS Groups 1 and 2 did not differ in terms of baseline characteristics. The perioperative mortality rate was not significantly different between the two groups (6.6% in group 1 vs 7.5% in group 2). The overall cumulative rates of sinus rhythm were 68.9% in group 1 and 88.5% in group 2 (not statistically significant). Biatrial contraction was assessed by transthoracic echocardiography in 70.4% of the patients in group 1 and 76.5% of the patients in group 2 (p = 0.65). CONCLUSIONS The RF ablation procedure offers as good results as the Cox/Maze III operation, allowing recovery of the sinus rhythm and atrial function in the great majority of patients with atrial fibrillation who underwent open heart surgery; it is a safe and effective means of curing atrial fibrillation with negligible technical and time requirements.

Phenotypic and genotypic heterogeneity in transthyretin-related cardiac amyloidosis: Towards tailoring of therapeutic strategies?

Transthyretin-related hereditary amyloidosis (ATTR) is genotypically/phenotypically heterogeneous. We investigated myocardial involvement in ATTR in a cohort of patients with a wide range of mutations. Clinical/echocardiographic follow-up of 41 consecutive symptomatic ATTR patients from a single referral center was analyzed according to TTR mutation. Diagnosis was based on histology, immunohistochemistry and genotyping. Median follow up was 40 months (range 8–120). Among the 12 different mutations identified, Val30Met was found in 10 patients and Glu89Gln in seven. Compared with Val30Met, Glu89Gln was associated with higher LV mass index, lower left ventricular ejection fraction and shorter E-wave deceleration time. All Glu89Gln carriers had cardiomyopathy, which was more severe (for left ventricular thickness, left ventricular mass and restrictive pathophysiology) than in the six affected Val30Met patients. Glu89Gln was independently associated with higher risk of major cardiovascular events among cardiomyopathy patients. This follow-up study of ATTR patients carrying a wide range of mutations indicates that (1) cardiac involvement is a very important component of phenotypic expression; and (2) genotype is an important source of heterogeneity in myocardial involvement, with Glu89Gln being associated with a severe, heart-driven prognosis. We think that combined heart–liver transplantation could be considered for Glu89Gln carriers with established, morphologically severe cardiomyopathy.

Extracorporeal Membrane Oxygenation for Primary Allograft Failure

OBJECTIVE Herein we have reported our experience concerning the usefulness of extracorporeal membrane oxygenation (ECMO) in heart transplant patients. PATIENTS AND METHODS Between July 2002 and March 2007, 11 heart transplant patients, namely, 8 men and 3 women of overall mean age of 49.4 +/- 13.9 years (range, 19-62 years) with primary graft failure underwent ECMO implantation. Two patients had pulmonary hypertension; 3 had been transplanted with hearts from marginal donors. At the time of implantation, all were in severe cardiogenic shock despite maximal inotropic support. In 6 patients, the ECMO was implanted centrally in the operating room when there was failure of weaning of cardiopulmonary bypass. Among the 5 remaining patients, ECMO was implanted peripherally in the intensive care unit, during the first 60 hours, including 3 cases of hemodynamic instability and 1 of irreversible cardiac graft arrest. The last patient was implanted on day 30 after transplantation because of acute rejection. RESULTS Mean pump outflow was 2.7 +/- 0.4 L/min/m(2). One patient died on circulatory support due to a cerebral hemorrhage. Ten patients were weaned from ECMO after a mean duration of 9.1 +/- 6.9 days (range, 1-18 days). All of them were successfully discharged. No retransplantation occurred. CONCLUSION Rapid operating room or bedside placement of ECMO allowed stabilization of hemodynamics with potential myocardial recovery in patients with cardiac graft failure.

Extracorporeal membrane oxygenation support in refractory cardiogenic shock: treatment strategies and analysis of risk factors.

Two centrifugal pumps, the RotaFlow (Maquet, Jostra Medizintechnik AG, Hirrlingen, Germany) and Levitronix CentriMag (Levitronix LCC, Waltham, MA, USA), used in central or peripheral veno-arterial extracorporeal membrane oxygenation (ECMO) support systems have been investigated, in terms of double-center experience, as treatment for patients with refractory cardiogenic shock (CS). Between January 2006 and December 2012, 228 consecutive adult patients were supported on RotaFlow (n=213) or CentriMag (n=15) ECMO, at our institutions (155 men; age 58.3±10.5 years, range: 19-84 years). Indications for support were: failure to wean from cardiopulmonary bypass in the setting of postcardiotomy (n=118) and primary donor graft failure (n=37); postacute myocardial infarction CS (n=27); acute myocarditis (n=6); and CS on chronic heart failure (n=40). A peripheral ECMO setting was established in 126 (55.2%) patients while it was established centrally in 102 (44.7%). Overall mean support time was 10.9±9.7 days (range: 1-43 days). Eighty-four (36.8%) patients died on ECMO. Overall success rate, in terms of survival on ECMO (n=144), weaning from mechanical support (n=107; 46.9%), bridge to mid-long-term ventricular assist device (n=6; 2.6%), and bridge to heart transplantation (n=31; 13.5%), was 63.1%. One hundred twenty-two (53.5%) patients were successfully discharged. Stepwise logistic regression identified blood lactate level and MB isoenzyme of creatine kinase (CK-MB) relative index at 72 h after ECMO initiation, and number of packed red blood cells (PRBCs) transfused on ECMO as significant predictors of mortality on ECMO (P=0.010, odds ratio [OR]=2.94; 95% confidence interval [CI]=1.10-3.14; P=0.010, OR=2.82, 95% CI=1.014-3.721; and P=0.011, OR=2.69; 95% CI=1.06-4.16, respectively). Central ECMO population had significantly higher rate of continuous veno-venous hemofiltration need and bleeding requiring surgery events compared with the peripheral ECMO setting population. No significant differences were seen by comparing the RotaFlow and CentriMag populations in terms of device performance. At follow-up, persistent heart failure with left ventricle ejection fraction (LVEF)≤40% was a risk factor after hospital discharge. Patients with a poor hemodynamic status may benefit from rapid central or peripheral insertion of ECMO. The blood lactate level, CK-MB relative index, and PRBCs transfused should be strictly monitored during ECMO support. In addition, early ventricular assist device placement or urgent listing for heart transplant should be considered in patients with persistent impaired LVEF after ECMO.

Activity–rest stimulation of latissimus dorsi for cardiomyoplasty: 1-year results in sheep

BACKGROUND In dynamic cardiomyoplasty electro-stimulation achieves full transformation of the latissimus dorsi (LD); therefore, its slowness limits the systolic support. Daily activity-rest could maintain partial transformation of the LD. METHODS Sheep LD were burst-stimulated either 10 or 24 hours/day. Before and 2, 4, 6, and 12 months after stimulation, LD power output, fatigue resistance, and tetanic fusion frequency were assessed. Latissimus dorsi were biopsied at 6 months, and sheep sacrificed at 12 months. RESULTS After 1 year of 10 hours/day stimulation LD was substantially conserved and contained large amounts of fast type myosin. From 2 months to 1 year of stimulation the power per muscle of the daily rested LD was greater than that of the left ventricle, being three to four times higher than in the 24-hour/day stimulation. CONCLUSIONS If extended to humans, these results could be the rationale for the need of a cardiomyostimulator, whose discontinuous activity could offer to patients the long-standing advantage of a faster and powerful muscle contraction.

New pathological insights into cardiac amyloidosis: implications for non-invasive diagnosis.

Background: Knowledge of the patterns of myocardial amyloid accumulation could improve the interpretation of electrocardiographic, echocardiographic and magnetic resonance imaging findings of amyloidosis. We assessed the extent and pattern of myocardial amyloid infiltration in explanted or autopsied hearts of patients with cardiomyopathy related to acquired monoclonal immunoglobulin light-chain (AL) or hereditary transthyretin (TTR) related amyloidosis (ATTR). Methods: We analyzed nine explanted/autopsied hearts from patients with AL (n = 4) and ATTR (n = 5) cardiac amyloidosis. For each heart, a biventricular histological macrosection was obtained at mid-ventricular level and analyzed with both inspective and computer-assisted histologic and histomorphometric analysis aimed in particular at quantifying muscle cells, fibrosis and amyloid infiltration. Results: The extent of amyloid infiltration of the left ventricle (LV) ranged from 45 to 76% (median [interquartile range (IQR)] = 57% [51–64]) of the overall surface. Although LV trabecular and subendocardial were the most infiltrated layers (45–94%, median [IQR] = 73% [67–84] and from 44 to 71%, median [IQR] = 57% [49–59], respectively), intra- and inter-patient heterogeneity was high. Three main patterns of amyloid infiltration of the LV were identified: diffuse (five cases), mainly subendocardial (two cases), and mainly segmental (two cases). The extent of amyloid infiltration of the right ventricle ranged from 48 to 93% (median [IQR] = 61% [59–83]); contributions of parietal and trabecular layers ranged from 32 to 99% (median [IQR] = 63% [47–88]) and from 49 to 93% (median [IQR] = 74% [64–79]), respectively. Conclusions: In amyloidotic cardiomyopathy, amyloid deposition is highly heterogeneous. Different patterns of infiltration are identifiable, including diffuse, mainly segmental and mainly subendocardial. Awareness of this variability can help the interpretation of ECGs, echocardiograms and magnetic resonance imaging.

Pulmonary endarterectomy: an alternative to circulatory arrest and deep hypothermia: mid-term results.

BACKGROUND The current surgical technique for pulmonary endarterectomy (PEA) involves the use of deep hypothermia and circulatory arrest at 18 degrees C (DHCA). Our experience started in 2004 when we decided to use an original alternative strategy which consists of avoiding deep hypothermia and subsequent circulatory arrest by using moderate hypothermia at 26 degrees C, and maintaining a bloodless field. This can be achieved by means of negative pressure in the left heart chambers and appropriate pump flow modulation in order to maintain the mixed venous oxygen saturation (SVO(2)) higher than 65%. MATERIALS AND METHODS From June 2004 to June 2007, 40 consecutive patients were operated on in our department with this strategy. The aim of this article is to report the early results for all patients and the complete six-month follow-up for 30 subjects who have reached this end-point at the time of writing. The mean temperature during extracorporeal circulation was 25.9 degrees C; core temperature was lowered to 21 degrees C in only one patient and an 8 min DHCA was performed in order to complete the PEA. RESULTS Two patients died (6.6%): one on the third postoperative day due to myocardial infarct, requiring an ECMO implantation. The other patient died from septic shock. The six-month follow-up, performed in all other patients, included clinical and hemodynamic evaluation. Pulmonary vascular resistance (PVR) decreased from 793.5+/-284 dyn/cm/s(-5) to 286+/-143 (p=0.000). A comparable reduction of mean pulmonary arterial pressure and an increase of cardiac output were also observed. CONCLUSIONS The results confirm that adequate removal of pulmonary artery obstructive lesions can also be achieved with an operative procedure that avoids or reduces the use of DHCA while allowing a bloodless field during PEA interventions. This technique may limit the well known adverse effects of DHCA due to organ hypoperfusion, improving the postoperative recovery of the patients.

Restored perfusion and reduced inflammation in the infarcted heart after grafting stem cells with a hyaluronan-based scaffold

The aim of this study is to investigate the blood perfusion and the inflammatory response of the myocardial infarct area after transplanting a hyaluronan‐based scaffold (HYAFF®11) with bone marrow mesenchymal stem cells (MSCs). Nine‐week‐old female pigs were subjected to a permanent left anterior descending coronary artery ligation for 4 weeks. According to the kind of the graft, the swine subjected to myocardial infarction were divided into the HYAFF®11, MSCs, HYAFF®11/MSCs and untreated groups. The animals were killed 8 weeks after coronary ligation. Scar perfusion, evaluated by Contrast Enhanced Ultrasound echography, was doubled in the HYAFF®11/MSCs group and was comparable with the perfusion of the healthy, non‐infarcted hearts. The inflammation score of the MSCs and HYAFF®11/MSCs groups was near null, revealing the role of the grafted MSCs in attenuating the cell infiltration, but not the foreign reaction strictly localized around the fibres of the scaffold. Apart from the inflammatory response, the native tissue positively interacted with the HYAFF®11/MSCs construct modifying the extracellular matrix with a reduced presence of collagene and increased amount of proteoglycans. The border‐zone cardiomyocytes also reacted favourably to the graft as a lower degree of cellular damage was found. This study demonstrates that the transplantation in the myocardial infarct area of autologous MSCs supported by a hyaluronan‐based scaffold restores blood perfusion and almost completely abolishes the inflammatory process following an infarction. These beneficial effects are superior to those obtained after grafting only the scaffold or MSCs, suggesting that a synergic action was achieved using the cell‐integrated polymer construct.

Stress Echocardiography as a Gatekeeper to Donation in Aged Marginal Donor Hearts: Anatomic and Pathologic Correlations of Abnormal Stress Echocardiography Results

BACKGROUND Owing to the shortage of donor hearts, the criteria for acceptance have been considerably expanded. Pharmacologic stress echocardiography is highly accurate in identifying prognostically significant coronary artery disease, but brain death and catecholamine storm in potential heart donors may substantially alter the cardiovascular response to stress. This study assessed correlates of an abnormal resting/stress echocardiography results in potential donors. METHODS From April 2005 to December 2007, 18 marginal candidate donors (9 men) aged 58 +/- 5 years were initially enrolled. After legal declaration of brain death, all marginal donors underwent bedside echocardiography, with baseline and (when resting echocardiography was normal) dipyridamole (0.84 mg/kg in 6 min) or dobutamine (up to 40 microg/kg/min) stress echo. Non-eligible hearts (with abnormal rest or stress echo findings) were excluded and underwent cardioautoptic verification. RESULTS Resting echocardiography showed wall motion abnormalities in 5 patients (excluded from donation). Stress echocardiography was performed in the remaining 13 (dipyridamole in 11; dobutamine in 2). Results were normal in 7, of which 6 were uneventfully transplanted in marginal recipients. Results were abnormal in 6, and autoptic verification performed showed coronary artery disease in 5, and initial cardiomyopathy in 1. CONCLUSIONS Bedside pharmacologic stress echocardiography can safely be performed in candidate heart donors, is able to unmask occult coronary artery disease or cardiomyopathy, and shows potential to extend donor criteria in heart transplantation. Further experience with using marginal donors is needed before exact guidelines can be established.

Arterial pressure changes monitoring with a new precordial noninvasive sensor

BackgroundRecently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2) amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes.MethodsThe transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99), dipyridamole (n = 41), or pacing stress (n = 6). The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value.ResultsA consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 ± 3.3 mg, increasing to 12.7 ± 7.7 mg at peak stress. S2 percentage increase was + 133 ± 104% in the 99 exercise, + 2 ± 22% in the 41 dipyridamole, and + 31 ± 27% in the 6 pacing patients (p < 0.05). Significant determinants of S2 amplitude were blood pressure, heart rate, and cardiac index with best correlation (R = .57) for mean pressure.ConclusionS2 recording quantitatively documents systemic pressure changes.