Synergy in the heart: RV systolic function plays a key role in optimizing LV performance during exercise.

The right ventricle (RV) is often overlooked in the evaluation of cardiac performance and treatment of left ventricular (LV) heart diseases. However, recent evidence suggests the RV may play an important role in maintaining systemic cardiac function and delivering stroke volume (SV). We used exercise cardiac magnetic resonance and biomechanical modeling to investigate the role of the RV in LV stroke volume regulation. We studied SV augmentation during exercise by pharmacologically inducing negative chronotropy (sHRi) in healthy volunteers and investigating training-induced SV augmentation in endurance athletes. SV augmentation during exercise after sHRi is achieved differently in the two ventricles. In the RV, the larger SV is driven by increasing contraction down to lower end-systolic volume (ESV; P < 0.001). In the LV, SV augmentation is achieved through an increase in end-diastolic volume (EDV; P < 0.001), avoiding contraction to a lower ESV. The same mechanism underlies the enhanced SV response observed in athletes. Changes in atrial area during SV augmentation suggest that the improved LV EDV response is sustained by the larger RV contractions. Using our biomechanical model, we explain this behavior by showing that the RV systolic function-driven regulation of LV SV optimizes the energetic cost of LV contraction and leads to minimization of the total costs of biventricular contraction. In conclusion, this work provides mechanistic understanding of the pivotal role of the RV in optimizing LV SV during exercise. It demonstrates why optimizing RV function needs to become a key part of therapeutic strategies in patients and training for athletes.NEW & NOTEWORTHY The right ventricle appears to have an important impact on maintaining systemic cardiac function and delivering stroke volume. However, its exact role in supporting left ventricular function has so far been unclear. This study demonstrates a new mechanism of ventricular interaction that provides mechanistic understanding of the key importance of the right ventricle in driving cardiac performance.

Contemporary epidemiology of infective endocarditis in patients with congenital heart disease: A UK prospective study.

OBJECTIVES: Infective endocarditis is a life-threatening complication of congenital heart disease (CHD), but there are few studies concerning the contemporary risk profile, preceding invasive procedures and outcomes in this patient population. The aim of this study was to investigate the epidemiology of infective endocarditis (IE) in patients with CHD. METHODS: Cases of IE in children and adults with CHD were prospectively recorded as part of the UK National Institute for Cardiovascular Outcomes Research (NICOR) National Congenital Heart Disease Audit. Patients were entered into the database between April 2008 and March 2016. RESULTS: Eight hundred episodes of IE were recorded in 736 patients with CHD. Sixty-five patients (9%) were infants (aged <1 year), 235 (32%) were children (aged 1-15 years), and 436 (59%) were adults (aged >15 years). The most common diagnoses were Tetralogy of Fallot (n = 150, 22.8%), ventricular septal defect (n = 129, 19.6%) and bicuspid aortic valve (n = 70, 10.7%). Dental procedures preceded 67 of 635 episodes (11%) of IE, and non-dental invasive procedures preceded 177 of 644 episodes (27.4%). The most common causative organisms were streptococci, accounting for 40% of cases. Overall in-hospital mortality was 6.7%. On multivariable analysis, adverse factors associated with in-hospital mortality were staphylococcal infection and presence of an underlying atrioventricular septal defect. CONCLUSIONS: Infective endocarditis in patients with CHD is an ongoing clinical challenge. In contemporary practice in tertiary congenital centers, 1 of 15 patients do not survive to hospital discharge. Streptococci remain the most common causative organism, and antecedent dental or medical procedures were undertaken in a significant minority in the 3 months before diagnosis. The presence of an atrioventricular septal defect or staphylococcal infection is associated with significantly increased risk of early mortality.

Prevalence of multidrug-resistant organisms in migrant children admitted to an Italian cardiac surgery department, 2015-2016.

Screening on hospital admission to identify multidrug-resistant organism (MDRO) colonization is a frequently discussed topic. We report the results of microbiological screening in 141 Italian and 354 migrant children candidates for cardiac surgery conducted in 2015-2016. In all, 25% of Italian children and more than 65.4% of African and Romanian children carried at least one MDRO (meticillin-resistant Staphylococcus aureus; extended-spectrum ß-lactamase enzymes; carbapenemase producers; and vancomycin-resistant enterococci). Based on our findings, we propose that non-geographically limited approaches are needed to improve infection prevention and control.

Vascular manifestations of syndromic aortopathies: role of current and emerging imaging techniques.

Patients with connective tissue diseases such as Marfan's syndrome, Loeys-Dietz syndrome, and vascular Ehlers-Danlos syndrome comprise a small but important group of patients who present early with acute aortic syndrome comprising aneurysmal dilation, rupture, or aortic dissection. Cardiovascular pathologies are an important yet treatable cause of morbidity and mortality in these patients. Imaging plays an important role in initial diagnosis, surveillance, and identification of complications. Furthermore, these patients are prone to developing complications in other vascular territories. Effective screening and surveillance will allow early diagnosis and elective treatment thus reducing the morbidity and mortality associated with presentation with acute complications. In this article, we will provide an overview of the role of magnetic resonance and computed tomography angiography in the management of syndromic aortopathies.

Prevalence of cerebral aneurysms in patients treated for left cardiac myxoma: a prospective study.

AIM: To estimate the prevalence of cerebral aneurysms in patients previously treated for left cardiac myxoma (LCM). MATERIALS AND METHODS: This prospective institutional review board-approved study included patients treated for LCM. All patients treated at our institution (IRCCS Policlinico San Donato, Italy) were telephoned and those enrolled underwent unenhanced brain magnetic resonance imaging (MRI) using sagittal T1-weighted turbo spin-echo (TSE); axial T2-weighted TSE; axial fluid-attenuated inversion-recovery; axial echo-planar diffusion-weighted; and three-dimensional time-of-flight angiographic sequences. RESULTS: Seventy-six patients were telephoned, and data regarding their clinical history since tumor resection were obtained for 49 patients (64%). Four of the 49 (8%) patients were deceased, one due to a cerebral hemorrhage from a ruptured cerebral aneurysm 8 years after tumor resection. One patient had a pacemaker preventing MRI. Of the remaining 44 patients, 31 refused MRI and 13 were enrolled (10 females; mean age 64 years). Three of the 13 (23%; two females; 59-78 years) were diagnosed with a cerebral aneurysm, from 2 mm to 4-5 mm in diameter, involving the right middle cerebral artery (n = 2) or the right internal carotid artery (n = 1). Including the deceased patient, the resulting prevalence was 4/14 (29%). CONCLUSION: From this preliminary study, one-third of patients treated for LCM may present with a cerebral aneurysm. Longitudinal large studies are needed to further clarify this matter.

Pattern of cerebral ultrasound in neonatal heart surgery.

AIM: No study described reliably the changes in cerebral ultrasound (CUS) findings in neonatal heart surgery. We tried to define the modifications of CUS before and after heart surgery in neonates. PATIENTS: We studied 48 neonates with congenital heart defects were studied. Of these, 33 had correction of the malformation with cardiopulmonary bypass (CPB group); 15 underwent coarctation repair/shunting procedures (no-CPB group). Patients had CUS pre-operatively, 48-72 hours after surgery, and at discharge. RESULTS: Pre-operative studies did not show significant differences between the groups. In CPB group, preoperatively, 6/33 infants showed echogenicity of basal ganglia and 1/33 grade I IVH. In the early postoperative evaluation, 24/33 infants had abnormal scans: increased echogenicity of basal ganglia in 24 and grade I IVH in 14. At discharge, abnormal scans persisted in 20/33 (basal ganglia echogenicity in 20, grade I IVH in 12). In the no-CPB group, preoperatively, 1/15 infant showed echogenicity of basal ganglia. In the early postoperative evaluation, 6/15 had abnormal scans: increased echogenicity of basal ganglia in 6, grade I IVH in 4. At discharge, abnormal scans persisted in 3/15. CONCLUSIONS: CUS after neonatal heart surgery shows a definite pattern of increased echogenicity of the basal ganglia, more consistent after CPB. These changes may reflect disturbances of deep grey matter, and last 10-15 days at least.

Perioperative heart failure in coronary surgery and timing of intra-aortic balloon pump insertion.

BACKGROUND: Perioperative heart failure (HF) in coronary operations is accompanied by a high operative mortality rate. An intra-aortic balloon pump (IABP) is often used to treat this syndrome. The correct timing for IABP insertion after completion of the operation has not yet been investigated. The aim of this study was to investigate the operative mortality in perioperative HF patients who had undergone coronary operations with respect to the early or the late use of IABP. METHODS: This is a retrospective study including 7,270 patients who had undergone coronary surgery with or without associated procedures. A population of patients with perioperative HF was extracted and analyzed with respect to the use of drugs, intra-operative or post-operative IABP to treat this condition. RESULTS: A total of 1,051 (14.5%) patients had perioperative HF. The mortality rate in this group was 13.5%. Early (intra-operative) IABP insertion was performed in 123 patients. In contrast, 928 patients were treated with inotropic drugs only, and, of these patients, 59 developed a drug-refractory HF requiring late IABP insertion. Operative mortality was significantly (P=0.001) higher in patients requiring late (64.4%) vs. early (41.5%) IABP insertion. Independent risk factors for developing a drug-refractory HF were age, pre-operative serum creatinine value and an associated mitral valve procedure. CONCLUSIONS: Postponing the use of IABP may be deleterious in patients with drug-refractory HF. In the presence of the three factors independently associated with the risk of a drug-refractory HF, early IABP insertion is suggested.

Effects of fenoldopam infusion in complex cardiac surgical operations: a prospective, randomized, double-blind, placebo-controlled study.

AIM: Fenoldopam mesylate is a short-acting dopamine-1 agonist that has been suggested to be a possible reno-protective agent in patients undergoing cardiac surgery. The present study is a prospective, randomized, double-blind placebo controlled trial conducted to determine the effects of fenoldopam in a population of patients undergoing complex cardiac operations. METHODS: Eighty subjects undergoing complex cardiac operations with cardiopulmonary bypass (CPB) were enrolled in the study. Patients were randomly assigned either to the fenoldopam (0.1 microg . kg-1. min-1) or the placebo group. Fenoldopam infusion started at the onset of CPB and was maintained for the first twelve postoperative hours. CPB parameters and renal outcome data were collected. RESULTS: Patients in the fenoldopam group had higher oxygen delivery during CPB and a significantly lower perfusion pressure, although this parameter was still within the normal range. Blood lactate concentrations during CPB were similar in the two groups. Urine output during and after CPB did not differ between groups, nor did the renal function parameters. There was a significantly higher rate of acute kidney injury (AKI) in the placebo group (10% vs 0%). In the subgroup of patients requiring inotropic support for more than 48 hours, renal function parameters were significantly better, the peak arterial blood lactate was significantly lower, and the major morbidity rate was significantly lower (36% vs 100%) for patients who received fenoldopam. CONCLUSION: Fenoldopam improves the quality of perfusion during CPB. In patients receiving catecholamines to treat a postoperative low cardiac output state, fenoldopam significantly improves renal function and prevents AKI and major morbidity.

[Surgical approach to adult with congenital heart disease]. / Trattamento chirurgico delle cardiopatie congenite nel paziente adulto.

The number of adults with congenital heart disease will inevitably increase in the near future. Recent data suggest that the number of adults with congenital heart disease, whether repaired or not, approaches the number of children with the disorder. Cardiac surgery in these patients presents major difficulties in management and technique. This especially applies to cardiac reoperation, which is one of the most frequent interventions and the most common cause of death in these patients. The present study reviews our experience with a large population of 811 consecutive patients who underwent cardiac operation or reoperation between January 2000 to December 2009 at our Institution.

Hypothermic cardiopulmonary bypass as a determinant of late thrombocytopenia following cardiac operations in pediatric patients.

BACKGROUND: Thrombocytopenia after cardiac operations is a common event in both adult and pediatric patients. Late thrombocytopenia (LTCP) is a less common event that is still without a well-recognized cause. This study explores the role of heparin-induced thrombocytopenia (HIT) and other factors (complexity of the operation, temperature management, and drug use) in determining LTCP. METHODS: We conducted an observational study of 63 consecutive patients aged <36 months operated with or without cardiopulmonary bypass (CPB). LTCP was defined as a platelet count <100,000 cells/microl or <50% of the pre-operative count at any point in time between post-operative days 5 and 10. A diagnostic test for heparin-platelet factor 4 (PF4) antibodies was performed in patients with LTCP. Other pre- and post-operative factors were investigated for their association with LTCP. RESULTS: LTCP occurred in 15 (24%) patients. No patient had positive heparin-PF4 antibodies. The lowest temperature on CPB was an independent predictor of LTCP, with a cut-off value at 29 degrees C (sensitivity 80%, specificity 70%). Other factors associated with LTCP were prolonged post-operative use of unfractionated heparin and milrinone. LTCP was associated with increased post-operative morbidity. CONCLUSION: LTCP was related to a combination of factors (operation severity, degree of hypothermia during CPB, prolonged use of unfractionated heparin, and milrinone). The individual contribution of each factor seems difficult to establish. However, the degree of hypothermia during CPB and drug-associated effects were identified. HIT could be excluded in all cases.

Predicting transfusions in cardiac surgery: the easier, the better: the Transfusion Risk and Clinical Knowledge score.

BACKGROUND AND OBJECTIVES: Allogeneic blood products transfusions are associated with an increased morbidity and mortality risk in cardiac surgery. At present, a few transfusion risk scores have been proposed for cardiac surgery patients. The present study is aimed to develop and validate a risk score based on adequate statistical analyses joint with a clinical selection of a limited (five) number of preoperative predictors. MATERIALS AND METHODS: The development series was composed of 8989 consecutive adult patients undergone cardiac surgery. Independent predictors of allogeneic blood transfusions were identified. Subsequently, five predictors were extracted as the most clinically relevant based on the judgement of 30 clinicians dealing with transfusions in cardiac surgery. A predictive score was developed and externally validated on a series of 2371 patients operated in another institution. The score was compared to the other existing scores. RESULTS: The following predictors constituted the Transfusion Risk and Clinical Knowledge score: age > 67 years; weight < 60 kg for females and < 85 kg for males preoperative haematocrit; gender--female; and complex surgery. At the external validation, this score demonstrated an acceptable predictive power (area under the curve 0.71) and a good calibration at the Hosmer-Lemeshow test. When compared to the other three existing risk scores, the Transfusion Risk and Clinical Knowledge score had comparable or better predictive power and calibration. CONCLUSION: A simple risk model based on five predictors only has a similar or better accuracy and calibration in predicting the transfusion rate in cardiac surgery than more complex models.

[Right ventricular restoration in adult patients after TOF surgery]. / Rimodellamento del ventricolo destro nel paziente Fallot adulto corretto.

OBJECTIVE: Pulmonary regurgitation may cause progressive right ventricular dilatation and dysfunction in adult patients previously repaired for tetralogy of Fallot. To assess the optimal surgical timing, the impact of the right ventricular restoration with a new surgical ventriculoplasty technique is evaluated following TFO repaired adult patients with severe pulmonary regurgitation and right ventricular dilatation. METHODS: Sixteen patients with severe pulmonary valve regurgitation (PVR) and right ventricular dilatation with RVOT aneurysm underwent right ventricular remodelling since January 2002. Each underwent preoperative evaluation by Doppler echocardiography, magnetic resonance imaging (MRI), and right ventricular myocardial acceleration during isovolumic contraction (IVC). The surgical procedure included pulmonary valve implantation and RVOT restoration achieved by removal of the aneurysm tissue, coupled with a ventriculoplasty to reduce volume, accomplished by creating a satisfactory RVOT dimension by placing with 2-0 Gortex suture to allow acceptance of a 26 Hegar dilator to avoid restriction. Nine patients had associated surgical procedures. RESULTS: All patients survived the operative procedure and underwent a 16-month follow-up interval. A reduction of cardio thoracic index and a clinical improvement occurred in each patient. Significant reduction of RVEDV and RVESV and increased right ventricular ejection fraction was observed. CONCLUSIONS: This preliminary database implies that the right ventricular restoration is a simple and effective procedure, and introduces a structural component that should be added in repaired TFO patients with right ventricular dilatation and underlying aneurysm or akinesia of the right ventricular outflow tract.

[Tetralogy of fallot: evolution of medical-surgical management (part 1)]. / Tetralogia di Fallot: evoluzione del management medico-chirurgico (Parte prima).

Despite Tetralogy of Fallot is a well-known cardiac congenital disease, still an important cardiovascular surgery and intensive care challenge. The following is a selective account of medical and surgical concepts and procedures; the emphasis is on therapeutic developments during the last 50 years. This review is divided into two parts: the first of which traces the evolution of medical and palliative techniques; the second part approaches the surgical corrections and try to explain the reinterventional causes and the residual defects responsible of cardiac failure.

[Tetralogy of Fallot: evolution of medical-surgical management (part 2)]. / Tetralogia di Fallot: evoluzioni del management medico-chirurgico (parte seconda).

This review is divided into two parts: the first of which traces the evolution of medical and palliative techniques; the following is a selective account of surgical concepts and procedures; the emphasis is on therapeutic developments during the last 50 years. The second part approaches the surgical corrections and tries to explain the reinterventional causes and the residual defects responsible of cardiac failure.

Octreotide in the management of postoperative chylothorax.

Chylothorax (KT) may be a complication of thoracic surgery. Its management is not well established and may comprise dietary interventions and surgery. The effectiveness of somatostatin and its analogues has been reported, although their mechanism(s) of action is unclear. We report our experience with octreotide in a series of patients with postoperative chylothorax. Eight patients with KT were treated with a continuous intravenous infusion of octreotide (OCT) at a starting dose of 0.5 microg/kg/hr. They were compared with four additional patients with KT who were treated according to the conventional approach. After a mean of 3.3 +/- 1.9 days of treatment, fluid discharge diminished dramatically. In all patients, fluid losses stopped by postoperative day 10.5 +/- 2.9 and chest tubes could be removed after 12.8 +/- 4.1 days. Compared to a small group of historical controls, OCT reduced significantly the total fluid losses (141.1 +/- 89.3 vs 396.7 +/- 151.0 ml/kg; p = 0.003) and the postoperative length of stay (p = 0.05). No patients in the group treated with OCT required parenteral nutrition (compared to all four of the controls; p = 0.002) and/or thoracenteses (compared to two of four controls). In postoperative KT, OCT seems to be at least as effective as the conventional approach. Furthermore, OCT may reduce total fluid losses and postoperative length of stay. This may have a beneficial effect on the risk of complications and on hospital costs.

Long-term outcome after senning operation for transposition of the great arteries.

BACKGROUND: The Senning operation for transposition of the great arteries (TGA) was first introduced by Senning in 1959 and was revived by Quaegebeur et al. in the late 1970s, thus becoming the intervention of choice for the correction of TGA in many centers. HYPOTHESIS: The purpose of this study was to evaluate the long-term follow-up of a group of patients undergoing surgery with the Senning procedure for TGA. METHODS: From November 1978 to November 1987, 73 consecutive patients underwent the Senning operation. The 70 survivors had an average follow-up of 19 years (16-25 years). RESULTS: (1) Cardiac rhythm: with time there was a progressive decrease in stable sinus rhythm (60% after 20 years) and a progressive increase of supraventricular tachyarrhythmias requiring therapy (10% after 20 years). (2) Right ventricular function: 20% of the patients had reduced ejection fraction. (3) Late mortality: in the last 12 years of follow-up years there were two sudden deaths (2.8%). (4) Functional status: 80% of patients were in NYHA class I, 17% in class II, and 3% in class III. CONCLUSIONS: Our results confirm that the patients who undergo the Senning procedure have a progressive loss of sinus rhythm, an increase in active arrhythmias, and other important adverse outcomes such as late sudden death and a decrease in right ventricular function; however, most patients (93% in our series) are alive and in good functional status.

Transcatheter closure of persistent ductus arteriosus with the Amplatzer duct occluder in very young symptomatic children.

OBJECTIVES: To analyse safety, efficacy, and follow up results of percutaneous closure of persistent ductus arteriosus (PDA) in very young symptomatic children. PATIENTS AND DESIGN: Between March 2000 and March 2003, of 197 patients treated at the authors' institution 18 were symptomatic children aged < or = 3 years old. Seven of these children were < or = 1 year old. Indications for closure were failure to thrive (12 patients) and frequent respiratory infections (six patients). The procedure was carried out under heavy sedation with fluoroscopic control. The Amplatzer duct occluder device was used. Basal physical examinations and echocardiograms were performed before the procedure and at follow up (three, six, and 12 months and yearly thereafter). RESULTS: Mean (SD) age was 18.3 (10) months and mean (SD) weight at closure was 9.1 (2.2) kg. Neither death nor any major complications occurred. Complications occurred in three patients aged < or = 1 year. Two patients had a mild inguinal haematoma. One patient had femoral artery thrombosis that was successfully treated by intravenous urokinase. The mean (SD) follow up was 12.8 (8.5) months. No problems occurred. Patients with recurrent respiratory infections had no significant recurrences and children who had failed to thrive had significantly increased growth. CONCLUSIONS: In experienced hands, percutaneous closure of moderate to large PDA in very young symptomatic children is safe, effectively closes the PDA, and solves clinical problems.

Pulmonary regurgitation is an important determinant of right ventricular contractile dysfunction in patients with surgically repaired tetralogy of Fallot.

BACKGROUND: Evaluation of right ventricular (RV) function in patients with pulmonary regurgitation (PR) after tetralogy repair remains challenging because of abnormal RV loading conditions. METHODS AND RESULTS: We examined 124 patients, aged 21+/-11.4 years, who had tetralogy repair at 3.7+/-3.5 years. By Doppler echocardiography, 33 patients had mild, 22 moderate, and 69 severe PR; 55 had significant tricuspid regurgitation (TR). Myocardial velocities, myocardial acceleration during isovolumic contraction (IVA), strain, and strain rate were measured at RV and LV base. Tricuspid valve annulus was measured in a 4-chamber view. QRS, QT, and JT intervals and their dispersions were measured from 12-lead electrocardiogram. IVA in the RV was lower in all patients compared with controls (0.8+/-0.4 versus 1.8+/-0.5, P<0.0001) and correlated with the severity of PR (r=-0.43, P<0.0001), whereas myocardial velocities, and strain/strain rate did not. LV IVA correlated with PR (r=-0.32, P<0.001) and with RV IVA (r=0.28, P<0.003). Patients with severe PR had a higher incidence of TR (r=0.69, P<0.0001) and lower RV IVA (1.0+/-0.4 versus 0.6+/-0.3, P<0.0001), a larger tricuspid valve ring diameter (P<0.0001), and prolonged electrical depolarization (P<0.001). Age at surgery or examination did not correlate with PR and with RV function assessed by IVA. In the RV, IVA correlated inversely with QRS duration (P<0.01). CONCLUSIONS: Although load-dependent myocardial velocities and strain are not influenced by the severity of PR and presence of significant TR, IVA demonstrates reduced contractile function in relation to the degree of PR and may be an early, sensitive index for selecting patients for valve replacement.