Erminio Sisillo

Hemofiltration as short-term treatment for refractory congestive heart failure

Hemofiltration has been suggested as a new therapeutic tool in refractory heart failure. In this study, 11 patients with primary or ischemic heart disease in New York Heart Association class IV, in whom there was no response to medical treatment, were subjected to hemofiltration. The pathophysiologic adjustments promoted by subtraction of plasma water were investigated, and guidelines for an appropriate use of this procedure in heart failure are provided. Fluid was removed from plasma at a rate of 500 ml/hour until either normalization of the right atrial pressure (which was increased in all cases) was achieved or the hematocrit exceeded 50 percent. According to these criteria, the duration of treatment ranged from four to six hours and the total amount of fluid removed was 2,000 to 3,000 ml. In each case, hemofiltration promoted relief of dyspnea and of clinical and radiographic evidence of lung congestion and pleural effusion, and substantially reduced the dependent edema and abdominal girth. These effects were paralleled by progressive decrease of the right (-70 percent) and left (-45 percent) ventricular filling pressures and of the pulmonary arterial pressure and arteriolar resistance, without significant variations in heart rate, aortic pressure, cardiac index, and systemic vascular resistance. Changes in the right atrial and wedge pulmonary pressures are interpreted as reflecting a combined effect of a decrease in pressure on the outside of the heart due to fluid reabsorption (from lung interstitial spaces and pericardial, pleural and abdominal cavities) and of intravascular volume subtraction. The arterial partial pressure of oxygen was raised, the partial pressure of carbon dioxide and pH were unchanged, and urinary output was substantially enhanced by the procedure. The study indicates that: hemofiltration may be a short-term treatment for refractory cardiac insufficiency with overhydration; a filtration rate of 500 ml/hour is effective and safe; and the central venous pressure may be a reliable guide to volume subtraction.

Cardiopulmonary bypass duration is an independent predictor of morbidity and mortality after cardiac surgery.

OBJECTIVE The aim of this study was to determine if there is a direct relationship between the duration of cardiopulmonary bypass (CPB time [CPBT]) and postoperative morbidity and mortality in patients undergoing cardiac surgery. DESIGN Retrospective study. SETTING Cardiac surgery unit, university hospital. PARTICIPANTS Five thousand six patients, New York Heart Association classes 1 through 4, who underwent cardiac surgery between January 2002 and March 2008. INTERVENTIONS All patients were subjected to CPB. MEASUREMENTS AND MAIN RESULTS The mean CPBT was 115 minutes (median 106). One hundred thirty-one patients (2.6%) died during the same hospitalization. The postoperative median blood loss was 600 mL. Reoperations for bleeding occurred in 193 patients (3.9%), and 1,001 patients received 3 or more units of red blood cells. There were 108 patients (2.2%) with neurologic sequelae, 391 patients (7.8%) with renal complications, 37 patients (0.7%) with abdominal complications, and 184 patients (3.7%) with respiratory complications. Seventy-two patients (1.4%) had an infective complication, and 80 patients (1.6%) had a postoperative multiorgan failure. The multivariate analysis confirmed the role of CPBT, considered in 30-minute increments, as an independent risk factor for postoperative death (odds ratio [OR] = 1.57, p < 0.0001), pulmonary (OR = 1.17, p < 0.0001), renal (OR 1.31, p < 0.0001), and neurologic complications (OR = 1.28, p < 0.0001), multiorgan failure (OR = 1.21, p < 0.0001), reoperation for bleeding (OR = 1.1, p = 0.0165), and multiple blood transfusions (OR = 1.58, p < 0.0001). CONCLUSIONS Prolonged CPB duration independently predicts postoperative morbidity and mortality after cardiac surgery.

N-acetylcysteine for prevention of acute renal failure in patients with chronic renal insufficiency undergoing cardiac surgery: a prospective, randomized, clinical trial.

Objective:To assess the preventive effect of the antioxidant N-acetylcysteine on postoperative acute renal failure in patients with renal insufficiency undergoing cardiac surgery. Design:Randomized, placebo-controlled, prospective study. Setting:University cardiology center. Patients:Two hundred fifty-four consecutive patients with chronic renal insufficiency (estimated creatinine clearance ≤60 mL/min) undergoing elective cardiac surgery. Interventions:Patients were randomized to receive N-acetylcysteine (n = 129) or placebo (n = 125). Patients of the N-acetylcysteine group received four boluses of intravenous N-acetylcysteine (1200 mg every 12 hrs, starting immediately before cardiac surgery). Measurements and Main Results:The incidence of postoperative acute renal failure (>25% increase in serum creatinine from baseline) and the in-hospital clinical course were evaluated. Acute renal failure occurred in 46% of patients and was associated with increased in-hospital mortality (7% vs. 0.7%; p = .024). It occurred in 52% of control patients and 40% of N-acetylcysteine-treated patients (p = .06). In-hospital mortality and need for renal replacement therapy were not affected by N-acetylcysteine, but a lower percentage of N-acetylcysteine-treated patients required mechanical ventilation prolonged for >48 hrs (3% vs. 18%; p < .001) and had an intensive care unit stay >4 days (13% vs. 33%; p < .001). Conclusions:Intravenous administration of N-acetylcysteine does not clearly prevent postoperative acute renal failure in patients with renal insufficiency undergoing cardiac surgery.

Quick, simple clamping technique in descending thoracic aortic aneurysm repair

BACKGROUND Although significant advances have been made in the surgical treatment of diseases affecting the descending thoracic aorta, paraplegia remains a devastating complication. We propose the quick, simple clamping technique to prevent spinal cord ischemic injury. METHODS From 1983 to 1998, 143 patients had descending thoracic aorta aneurysm repair. We divided the patients into the following three groups according to the surgical technique used: selective atriodistal bypass was used in group 1 (66 patients); simple clamping technique in group 2 (28 patients); and quick simple clamping technique in group 3 (49 patients). Mean aortic cross clamp time was 39+/-13 minutes in group 1, 37+/-11 minutes in group 2, and 17+/-6 minutes in group 3 (p<0.01 group 3 versus group 1 and group 2). RESULTS The overall incidence of paraplegia was 4.8% (7 patients), 4.5% (3 patients) in group 1, 14.3% (4 patients) in group 2, and 0 in group 3 (p<0.05 group 3 versus group 2). The overall in-hospital mortality rate was 5.5%. Multivariate logistic regression analysis showed a powerful effect of aortic cross-clamping time as risk factor for both paraplegia (p<0.008), with an odds ratio of 1.03 per minute, and in-hospital mortality (p<0.001), with an odds ratio of 2.5 per minute. The mean follow-up time was 65 months with a lower overall mortality rate in group 3 than in group 1 and group 2 (p<0.05). CONCLUSION In descending thoracic aortic aneurysm repair, spinal cord perfusion can be maintained adequately without reimplantation of segmental vessels or use of atriodistal bypass when the aortic cross-clamp time is short (<15 to 20 minutes).

Percutaneous pericardiocentesis versus subxiphoid pericardiotomy in cardiac tamponade due to postoperative pericardial effusion

In a retrospective study, 42 patients with acute cardiac tamponade due to pericardial effusion were evaluated following cardiac surgery, and the pericardial fluid was drained by one of two alternative methods: two-dimensional echocardiographic-guided pericardiocentesis (2D-echo) or subxiphoid surgical pericardiotomy. During the first period (from 1982 to 1986), one of the two methods was chosen by the treating physicians, whereas in the second period (from 1986 to 1991), 2D-echo-guided pericardiocentesis was the treatment of choice. Percutaneous pericardiocentesis was performed using local anesthesia in 29 patients. A Tuohy needle was inserted at the left xipho-costal junction and, when fluid was obtained, 6 mL of saline solution was injected during 2D-echo contrast monitoring, and a multiple-hole, 6F, 30-cm catheter was inserted by means of a guidewire and positioned into the posterior pericardium, as near as possible to the atrioventricular groove. Complete drainage of pericardial fluid by percutaneous pericardiocentesis was obtained in 26 patients (89%). This procedure also allowed the evacuation of posterior and loculated effusions. Complications included two right ventricular punctures, which were immediately recognized by 2D-echo contrast and produced no serious consequences. Sixteen patients who underwent surgical pericardiotomy had complete evacuation of pericardial fluid without major complications (two of them suffered atrial arrhythmias during the procedure). The average amount of fluid drained, as well as the localization of the effusions, were the same for both groups. 2D-echo-guided pericardiocentesis was found to be a useful, safe, and simple technique. It can be used as an alternative treatment to subxiphoid pericardiotomy for cardiac tamponade due to postoperative pericardial effusions.

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.

Pre-operative transthoracic real-time three-dimensional echocardiography in patients undergoing mitral valve repair: accuracy in cases with simple vs. complex prolapse lesions

AIMS The aim of this study, undertaken in patients who underwent mitral valve (MV) repair surgery, was to evaluate the accuracy of pre-operative three-dimensional (3D) transthoracic echocardiography (TTE) in the evaluation of MV pathology in cases with simple or complex lesions. METHODS AND RESULTS Two hundred consecutive patients with severe mitral regurgitation due to degenerative MV prolapse underwent a complete 3DTTE the day before surgery. Three-dimensional TTE data were compared with MV surgical inspection. Three-dimensional echocardiography was feasible in a relatively short time (5 ± 3 min) with good (67%) and optimal (21%) imaging quality in the majority of cases. Three-dimensional TTE allowed an accurate identification (95% accuracy) of all MV lesions. Seventy-three (36.5%) patients had simple lesions at 3DTTE and 71 of them (97.2%) underwent a simple surgical procedure; 127 (63.5%) had complex lesions at 3DTTE and, in these cases, surgeons performed either simple procedures (48%) or complex procedures (47.2%) or valve replacement in 4.7% (after a first attempt for repair). CONCLUSION Three-dimensional TTE is feasible, not time-consuming, and accurate in identifying cases with simple vs. complex MV lesions.

Isolated ultrafiltration in cardiogenic pulmonary edema

Twenty patients (ten with mitral and/or aortic valve disease and ten with ischemic heart disease, all in the New York Heart Association class IV, aged between 18 and 74 yr, with cardiogenic pulmonary edema unresponsive to drug treatment) were treated with polysulphone membrane ultrafiltration (UF) in a veno-venous circuit. All patients had dyspnea, pulmonary rales, hypoxemia, tachycardia, hypotension, overhydration, radiologic evidence of engorged pulmonary vasculature, and Kerley-B lines.Systemic and pulmonary arterial pressures, cardiac output (by thermodilution), and intrapulmonary shunt fraction (Qsp/Qt) were determined and chest x-ray was obtained at the beginning and the end of UF. Average duration of the treatment was 150 ± 28 min; UF volume averaged 3000 ± 170 ml. UF reduced the Qsp/Qt by 58% from control condition, and did not significantly affect hemodynamic variables. Chest x-rays documented clearing of alveolar edema and venous congestion. These changes were associated with unequivocal clinical improvement and no mechanical ventilation was necessary to improve gas exchange. Short-term fluid subtraction did not result in undesired circulatory alterations. Because the ultrafiltrate composition is similar to plasmatic fluid, no modification in the plasma osmolarity was detected.In conclusion, UF may be considered an effective tool for the treatment of acute pulmonary edema refractory to drug therapy, as an alternative to mechanical ventilation, and as a remedy for excessive extravascular lung water.

Cardiopulmonary bypass and oxygen consumption: oxygen delivery and hemodynamics

BACKGROUND This study was undertaken to investigate the relations between whole body oxygen consumption (VO2), oxygen delivery (DO2), and hemodynamic variables during cardiopulmonary bypass. METHODS One hundred one patients were studied during cooling, hypothermia, and rewarming. Oxygen consumption, DO2, hemodynamics, and DO2crit were measured at these times. RESULTS There was a direct linear relation between DO2 and VO2 during all three times. No relation between VO2 and hemodynamics was detected during cooling; during hypothermia, an inverse linear relation with peripheral arterial resistance was found. Finally, during rewarming, there was a direct relation with pump flow rate, and an inverse relation with arterial pressure and arterial resistance. The same relations among the variables were found at delivery levels above or below DO2crit. CONCLUSIONS During cardiopulmonary bypass there is a direct linear relation between DO2 and VO2; the relations with hemodynamic variables depend on the phases of cardiopulmonary bypass. This suggests that increasing delivery levels may recruit and perfuse more vascular beds, and higher delivery levels are advisable during perfusion. During rewarming and hypothermia, lower arterial resistances are also desirable to optimize VO2.

Left Main Coronary Artery Occlusion After Percutaneous Aortic Valve Implantation

Left main coronary artery occlusion occurred immediately after transfemoral aortic valve implantation in an 87-year-old woman, which resulted in ventricular fibrillation and hemodynamic collapse. This life-threatening complication was promptly diagnosed with transesophageal echocardiography, which showed the disappearance of diastolic left main coronary artery jet flow and was confirmed with aortic root angiography. After prompt defibrillation, hemodynamic support was obtained with intra-aortic balloon pump and inotropic drugs. Functional recovery and survival were achieved with coronary stenting. This report highlights the importance of an integrated team approach of highly skilled specialists for these novel interventions.