Biventricular Contractility Research Articles

PERCUTANEOUS LEFT STELLATE GANGLION BLOCK TO INCREASE VENTRICULAR FIBRILLATION THRESHOLD AND DEFIBRILLATION SUCCESS RATE IN ACUTE FULMINANT MYOCARDITIS WITH ELECTRICAL STORM

Abstract Introduction Acute fulminant myocarditis represents a predisposing substrate for life–threatening ventricular arrhythmias (VAs). Percutaneous left stellate ganglion block (PLSGB) usage has been reported for the prevention of recurrent VAs, but clinical data on its acute effect on ongoing ventricular fibrillation (VF) are missing. Case A 57–years–old man suffering gastroenteritis and fever in the past week presented in the ED with typical chest pain. ECG depicted infero–lateral ST–segment elevation, cardiac ultrasound showed a mildly reduced LVEF and coronary angiography ruled out coronary lesions. In the following hours the patient developed frequent premature ventricular complexes with R on T phenomenon triggering short coupled torsade de pointes with rapid degeneration into VF. VAs episodes, initially responsive to single DC shock, kept recurring despite intravenous (iv) amiodarone, iv lidocaine and iv correction of potassium and magnesium. The patient was therefore treated with deep sedation, intubation and ECMO VA placement; still, he reached a status of persistently ongoing VF, refractory even to DC shocks (n=20). Therefore, ultrasound–guided PLSGB using a local bolus of lidocaine 150 mg + ropivacaine 50 mg was performed. After 5 minutes, a single DC shock was delivered, effective in achieving a stable sinus rhythm at 35 bpm with no more recurrences. Despite electrical stabilization, the patient developed a severe cardiogenic shock due to bradycardia and severe biventricular disfunction, treated with vasopressin and dobutamine. In the next 48 hours we observed a significant improvement, resumption of biventricular contractility and absence of VAs recurrences, so the patient was slowly weaned off ECMO and vasopressors. Immunological tests showed Enterovirus IgM positivity, while endomyocardial biopsy was negative for inflammatory infiltrates in the analyzed sections. Cardiac MRI (performed 10 days after onset) showed edema and non–ischemic LGE in the antero–lateral and infero–lateral basal subepicardial regions of the left ventricle, LVEF was 55%. After 15 days from admission, despite ongoing amiodarone and bisoprolol, the patient developed a run of monomorphic VA of 30 beats at 170 bpm, therefore he underwent sICD implantation. Conclusion PLSGB played a key role for the acute management of refractory VF unresponsive to DC shocks, allowing for acute stabilization. More clinical data are needed on acute neuromodulation for electrical storm.

Severe Refractory Vasoplegic Shock Syndrome after OPCABG Successfully Treated with Hydroxycobalamin: A Case Report and Review of the Literature.

Vasoplegic shock syndrome (VSS) after an off-pump coronary artery bypass graft (OPCABG) is an extremely rare condition. Inotropic support is usually the first-line therapy, though it can precipitate several complications or be ineffective. We report the first case of severe refractory VSS after OPCABG successfully treated with hydroxycobalamin. A 77-year-old gentleman underwent OPCABG for three vessels coronary artery disease. Preoperative LV ejection fraction was 28%, and the patient before surgery started sacubitril/valsartan titrated, then, at the highest dose. Surgery was uneventful and, by the end of the procedure, TEE showed improved biventricular contractility. The patient was transferred to the ICU without inotropic support, but soon developed hypotension. TEE ruled out pericardial tamponade and confirmed fair contractility. Norepinephrine was titrated to a medium-high dose, vasopressin was started and a Swan-Ganz catheter was placed. SVR was 480 dyn·s·cm-5. Despite aggressive pharmacologic treatment (including methylprednisolone and methylene blue), no improvements were noticed. Ten grams of hydroxycobalamin were administered. One hour later, hemodynamic status re-assessment showed SVR > 800 dyn·s·cm-5. Afterward, vasopressors were gradually reduced. Our case demonstrated the importance of adequate early treatment in VSS after OPCABG. This case report shows, for the first time, that hydroxycobalamin was effectively used to restore homeostasis.

Ex-situ oxygenated hypothermic machine perfusion in donation after circulatory death heart transplantation following either direct procurement or in-situ normothermic regional perfusion

Heart transplantation in donation after circulatory death (DCD) relies on warm perfusion using either in situ normothermic regional perfusion (NRP) or ex situ normothermic machine perfusion. In this study, we explore an alternative: oxygenated hypothermic machine perfusion (HMP) using a novel clinically applicable perfusion system, which is compared to NRP with static cold storage (SCS). In a porcine model, a DCD setting was simulated, followed by either (1) NRP and SCS (2) NRP and HMP with the XVIVO Heart preservation system or (3) direct procurement (DPP) and HMP. After preservation, heart transplantation (HTX) was performed. After weaning from cardiopulmonary bypass (CPB), biventricular function was assessed by admittance and Swan-Ganz catheters. Only transplanted hearts in the HMP groups showed significantly increased biventricular contractility (end-systole elastance) 2 hour post-CPB (left ventricle absolute change: NRP HMP: +1.8 ± 0.56, p=0.047, DPP HMP: +1.5 ± 0.43, p=0.045 and NRP SCS: +0.97 ± 0.47 mmHg/ml, p=0.21; right ventricle absolute change: NRP HMP: +0.50 ± 0.12, p=0.025, DPP HMP: +0.82 ± 0.23, p=0.039 and NRP SCS: +0.28 ± 0.26, p=0.52) while receiving significantly less dobutamine to maintain a cardiac output >4l/min compared to SCS. Diastolic function was preserved in all groups. Post-HTX, both HMP groups showed significantly less increments in plasma troponin T compared to SCS. In DCD HTX, increased biventricular contractility post-HTX was only observed in hearts preserved with HMP. In addition, the need for inotropic support and signs of myocardial damage were lower in the HMP groups. DCD HTX can be successfully performed using DPP followed by preservation with HMP in a preclinical setting.

Hemodynamics and Kinetics of Heart Failure with Preserved Ejection Fraction Shock

The classical paradigm of cardiogenic shock is severe impairment of left ventricular, right ventricular, or biventricular contractility resulting in decreased cardiac output and end-organ failure. In patients with preserved ejection fraction, cardiogenic shock results from impaired left ventricular filling leading to decreased cardiac output and end-organ hypoperfusion. Heart failure with preserved ejection fraction (HFpEF) comprises a heterogenous group of myocardial and systemic metabolic derangements. Cardiogenic shock with preserved left ventricular ejection is thought to be less common than with reduced left ventricular ejection fraction, and therapeutic approaches are not well standardized. We aim to review the pathophysiology of cardiogenic shock in HFpEF, define various etiologies that culminate in the HFpEF shock state, and present our algorithmic approach to managing these complex patients.

Disorganization of intercalated discs in dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is a primary myocardial disease, the pathology of which is left ventricular or biventricular dilation and impaired myocardial contractility. The clinical and pathological diagnosis of DCM is difficult, and other cardiac diseases must be ruled out. Several studies have reported pathological findings that are characteristic of DCM, including cardiomyocyte atrophy, nuclear pleomorphism, and interstitial fibrosis, but none of these findings are DCM-specific. In this study, we examined the morphological differences in the intercalated discs (ICDs) between three groups of patients, a DCM group, a chronic heart failure group, and a control group. A total of 22 autopsy cases, including five DCM cases, nine CHF cases and eight control cases, were retrieved from the archives of the Department of Pathology at Akita University, Japan. The morphological differences were examined using multiple methods: macroscopic examination, light microscopy, immunohistochemistry, electron microscopy, and gene expression analyses. We observed disorganized ICDs, clearly illustrated by N-cadherin immunostaining in the DCM group. “Reduction of N-cadherin immunostaining intensity” and “ICD scattering” was DCM-specific. The results suggest that disorganized ICDs contribute to the development of DCM, and that N-cadherin immunostaining is useful for determining the presence of disorganized ICDs and for the pathological diagnosis of DCM.

Reduced biventricular contractility during exercise in adults with small, unrepaired ventricular septal defects: an echocardiographic study.

Small ventricular septal defects are often considered to be without long-term haemodynamic consequences and so the majority remains unrepaired. However, we recently showed reduced functional capacity and altered right ventricular morphology in adults with small, unrepaired ventricular septal defects. The underlying mechanisms behind these findings remain unclear, and so, biventricular contractility during exercise was evaluated. Adults with small, unrepaired ventricular septal defects and healthy controls were examined with echocardiography during supine bicycle exercise with increasing workload. Tissue velocity Doppler was used for evaluating isovolumetric acceleration and systolic velocities during exercise. In total, 34 patients with ventricular septal defects, a median shunt- ratio of 1.2 (26 ± 6 years), and 28 healthy peers (27 ± 5 years) were included. Right ventricular isovolumetric acceleration was lower in patients as compared with controls at rest (97 ± 40 vs 158 ± 43 cm/s2, P = 0.01) and at peak heart rate (222 ± 115 vs 410 ± 120 cm/s2, P < 0.01). Peak systolic velocities were similar at rest, but differed with exercise (13 ± 3 vs 16 ± 3 cm/s, P = 0.02). Left ventricular isovolumetric acceleration was lower in patients as compared with controls throughout the test (P < 0.01). Septal isovolumetric acceleration was similar at rest, but reduced during increasing exercise as compared with controls (220 ± 108 vs 303 ± 119 cm/s2, P = 0.03). Left ventricular isovolumetric acceleration was negatively correlated with the shunt- ratio, and right ventricular and septal peak systolic velocities were positively correlated with lower functional capacity. Altered biventricular contractility is present during exercise in adults with small, unrepaired ventricular septal defects. These results add to the growing number of studies showing that long-term outcome in unrepaired ventricular septal defects may not be benign.

P3684Detecting true left dominant arrhythmogenic cardiomyopathy: cardiac magnetic resonance imaging and an invasive diagnostic assessment to go beyond current diagnostic criteria

Abstract Background Left-dominant arrhythmogenic cardiomyopathy (LDACM) represents an underdiagnosed subtype of the classical right-dominant ACM, with a fibro-fatty infiltration of the left ventricle ab disease initio. To date, ACM diagnosing criteria do not include any paradigm for LDACM and no shared consensus or position statement has been issued yet. Purpose To analyse the diagnostic work-up needed to reach a definite diagnosis in LDACM patients (pts). Methods All pts with a high clinical suspicion of ACM admitted at our institution were evaluated. Disease and familiar history, and both baseline ECG and cardiac ultrasound (US) were retrieved in all pts. Before invasive evaluation, all pts underwent cardiac magnetic resonance imaging (MRI) for morphology assessment and tissue characterization by late gadolinium enhancement (LGE). An invasive evaluation with an electrophysiological study (EPS) and an endo-cavitary electro-anatomical mapping (EAM) was then subsequently performed; EAM-guided endo-myocardial biopsy (EMB) was performed at physician discretion, for direct histological evaluation of myocardial substrate. Results 30 ACM pts (53±6 y.o.; 66% male) were defined as LDACM; 22 (73%) pts presented unspecific ECG abnormalities, with 8 (27%) pts instead presenting negative t-waves in V4-V6. Cardiac US resulted unremarkable in 27 (90%) pts. Sustained ventricular arrhythmia with right bundle brunch block were experienced in 4 (14%) pts, while frequent premature ventricular beats with the same morphology in 10 (33%). LDACM diagnosis was mainly suspected upon MRI evaluation: all 30 pts presented a late gadolinium enhancement (LGE) pattern revealing an isolate left ventricle fibro-fatty infiltration, with normal biventricular contractility (LV and RV ejection fraction 57±9% and 53±2%, respectively). Right ventricular, left ventricular and biventricular endo-cavitary EAM was performed in 10 (33%), 11 (37%) and 9 (30%) pts respectively, revealing pathologically low unipolar voltages in 7 (23%) and both unipolar and bipolar low voltages in 15 (50%) pts. In 18 (60%) pts an EMB was performed, revealing in 15 (83%) a fibro-fatty infiltrate and a fibro-fatty infiltrated with a superimposed viral myocarditis in a single pt. Genetic testing was performed in 16 (53%) pts, of which 10 (33%) showed causative mutation of desmosomal genes. If strictly adhering to the existing criteria, only 7 (23%) LDACM definite diagnosis would have been reached, even when using EMB and genetic testing. LDACM EAM with late potentials Conclusion LDACM is an underestimated ACM subtype that require MRI evaluation and an invasive work-up for definite diagnosis. Although EMB and genetic testing being the most effective diagnostic tools currently at disposal adhering to existing criteria, a definite diagnosis could be reached only in a fraction of patient population. Existing diagnostic criteria should be revised, mainly to take in consideration EAM specific role and to properly define the LDACM entity.

Anesthetic Management of an Elderly Patient with Dilated Cardiomyopathy and Hypothyroidism for Inter-Trochanteric Fracture

&#x0D; Dilated cardiomyopathy is a primary myocardial disease charac­terized by left ventricular or biventricular dilation and impaired contractility. The anesthetic management of a patient with dilat­ed cardiomyopathy undergoing a non-cardiac surgery is always challenging and may be associated with high mortality. Further­more, perioperative morbidity becomes more frequent in the el­derly with steep increases after the age of 75. We are reporting the successful anaesthetic management of a 93 years old patient with severe dilated cardiomyopathy planned for surgical repair of inter-trochanteric fracture under combined spinal anesthesia.

Biventricular contractility during exercise in adults with small, unrepaired atrial septal defects.

Adult patients with a small, unrepaired atrial septal defect (ASD) have higher mortality and increased risk of several comorbidities compared to general population. Further, reduced submaximal and peak exercise capacity was recently demonstrated in these patients. The mechanisms behind these findings remain unexplained and, therefore, biventricular contractility during exercise was assessed by evaluating the force-frequency relationship in the same group of patients. Adults patients with a small, unrepaired ASD and healthy age- and gender-matched controls were examined using echocardiography during supine bicycle exercise. Continuous tissue velocity Doppler was used to evaluate isovolumetric acceleration (IVA) and systolic velocities during an incremental workload protocol. All data were analyzed post hoc in a blinded fashion. We included 30 patients previously diagnosed with a small, unrepaired ASD (mean age 35years, 63% female) and 25 controls (mean age 34years, 64% female). Patients had similar values of IVA and systolic velocities at rest when compared with the healthy controls. Further, no differences in IVA was found at peak heart rate for neither the left ventricle (90±39 vs 129±68cm/s2 , P=0.1547) nor the right ventricle (128±56 vs 154±56cm/s2 , 0.5691). There were no correlations between peak velocities and the lower exercise capacity previously reported in these patients. Adult patients with a small, unrepaired ASD have normal biventricular contractility at rest and during exercise when compared with healthy peers. Consequently, the pathophysiological mechanisms behind the impaired exercise capacity previously demonstrated in these patients remains unknown and will be a target for future work.

Graded epidural anaesthesia for caesarean section in a parturient with severe left ventricular dysfunction from dilated cardiomyopathy: A case report

Dilated cardiomyopathy (DCM) is a primary disorder of heart muscle characterised by left ventricular (LV) or biventricular dilatation and impaired ventricular contractility. During pregnancy, women with DCM have a higher incidence of cardiac events than the non-pregnant patient. When DCM is associated with severe LV dysfunction, anaesthetic management is particularly challenging, because severe LV dysfunction is a predictor of sudden cardiac death and poor quality of life. The goals of anaesthetic management in DCM consist of maintaining normovolaemia, and avoiding myocardial depression and drug overdose during induction (as circulation time is slow). It also includes preventing increases in ventricular afterload and sudden hypotension when regional anaesthesia is a choice. This case report describes the successful anaesthetic management of a parturient with DCM and a severely low LV ejection fraction of 20%, wherein the child was delivered via caesarean section using a graded epidural anaesthesia technique.

Is there a place for intra-aortic balloon counterpulsation support in acute right ventricular failure by pressure-overload?

BackgroundMost therapeutic strategies for acute right ventricular failure (RVF) by pressure-overload are directed to improve cardiac output and coronary perfusion pressure by vasopressive agents. The eventual role of intra-aortic balloon counterpulsation (IABP) support remains questionable. This study investigates the contribution of IABP for acute RVF by pressure-overload, in comparison with phenylephrine (PE) and norepinephrine (NOR). MethodsAcute RVF is induced by fixed pulmonary artery constriction in 6 pigs, pursuing a 50% reduction of cardiac output. Assessment of the treatment interventions included biventricular PV-loop analysis, and continuous measurement of aortic and right coronary artery flow. ResultsRestoration of baseline cardiac output was only observed by administration of NOR (Baseline=3.82±1.52ml/min — RVF=2.03±0.59ml/min — IABP=2.45±0.62ml/min — PE=2.98±0.63ml/min — NOR=3.95±0.73ml/min, p<0.001). NOR had most effect on biventricular contractility (PRSW-slope-RV: IABP +24% — PE +59% — NOR +208%, p<0.001 and PRSW-slope-LV: IABP +36% — PE +53% — NOR +196%, p<0.001), heart rate acceleration (IABP +7% — PE +12% — NOR +51%, p<0.001), and RCA flow (IABP +31% — PE +58% — NOR +180%, p<0.001), concomitant to a higher increase of LV-to-RV pressure ratio (IABP: +7% versus −3%, PE: +36% versus +8%, NOR: +101% versus 42%). The hemodynamic contribution of IABP was limited, unless a modest improvement of LV compliance during PE and NOR infusion. ConclusionIn a model of acute pressure-overload RV failure, IABP appears to offer limited hemodynamic benefit. The administration of norepinephrine is most effective to correct systemic output and myocardial perfusion through adding an inotropic and chronotropic effect to systemic vasopression.

Effects of milrinone and epinephrine or dopamine on biventricular function and hemodynamics in right heart failure after pulmonary regurgitation.

Right ventricular failure (RVF) secondary to pulmonary regurgitation (PR) impairs right ventricular (RV) function and interrupts the interventricular relationship. There are few recommendations for the medical management of severe RVF after prolonged PR. PR was induced in 16 Danish landrace pigs by plication of the pulmonary valve leaflets. Twenty-three pigs served as controls. At reexamination the effect of milrinone, epinephrine, and dopamine was evaluated using biventricular conductance and pulmonary catheters. Seventy-nine days after PR was induced, RV end-diastolic volume index (EDVI) had increased by 33% (P = 0.006) and there was a severe decrease in the load-independent measurement of contractility (PRSW) (-58%; P = 0.003). Lower cardiac index (CI) (-28%; P < 0.0001), mean arterial pressure (-15%; P = 0.01) and mixed venous oxygen saturation (SvO2) (36%; P < 0.0001) were observed compared with the control group. The interventricular septum deviated toward the left ventricle (LV). Milrinone improved RV-PRSW and CI and maintained systemic pressure while reducing central venous pressure (CVP). Epinephrine and dopamine further improved biventricular PRSW and CI equally in a dose-dependent manner. Systemic and pulmonary pressures were higher in the dopamine-treated animals compared with epinephrine-treated animals. None of the treatments improved stroke volume index (SVI) despite increases in contractility. Strong correlation was detected between SVI and LV-EDVI, but not SVI and biventricular contractility. In RVF due to PR, milrinone significantly improved CI, SvO2, and CVP and increased contractility in the RV. Epinephrine and dopamine had equal inotropic effect, but a greater vasopressor effect was observed for dopamine. SV was unchanged due to inability of both treatments to increase LV-EDVI.

A retrospective comparison of aerosolized milrinone and aerosolized iloprost in the setting of post bypass pulmonary hypertension

Background & Aim. Right ventricular failure (RVF) secondary to pulmonary regurgitation (PR) impairs right ventricular (RV) function and interrupts the interventricular relationship. There are few recommendations for the medical management of severe RVF after prolonged PR. Methods. PR was induced in 16 Danish landrace pigs by plication of the pulmonary valve leaflets. Twenty-three pigs served as controls. At re-examination the effect of milrinone, epinephrine and dopamine was evaluated using biventricular conductance and pulmonary catheters. Results. Eighty-one days after PR was induced, RV enddiastolic volume index (EDVI) had increased by 33% (p1⁄40.006) and a severe decrease in the load-independent measurement of contractility (PRSW) (-58%; p1⁄40.003). Lower cardiac index (CI) (-28%; po0.0001), mean arterial pressure (-15%; p1⁄40.01) and mixed venous oxygen saturation (SvO2) (36%; po0.0001) were observed compared to the control group. The interventricular septum deviated towards the left ventricle (LV). Milrinone improved RV-PRSW and CI and maintained systemic pressure while reducing CVP. Epinephrine and dopamine further improved biventricular PRSW and CI equally in a dose-dependent manner. Systemic and pulmonary pressures were higher in the dopamine-treated animals compared to epinephrine-treated animals. None of the treatments improved stroke volume index (SVI) despite increases in contractility. Strong correlation was detected between SVI and LV-EDVI, but not SVI and biventricular contractility. Conclusion. In RVF due to PR, milrinone significantly improved CI, SvO2 and CVP and increased contractility in the RV. Epinephrine and dopamine had equal inotropic, but a greater vasopressor effect was observed for dopamine. SV was unchanged due to inability of both treatments to increase LVEDVI.

Effects of milrinone and epinephrine or dopamine on biventricular function and hemodynamics in an animal model with right ventricular failure after pulmonary artery banding

Right ventricular (RV) failure due to chronic pressure overload is a main determinant of outcome in congenital heart disease. Medical management is challenging because not only contractility but also the interventricular relationship is important for increasing cardiac output. This study evaluated the effect of milrinone alone and in combination with epinephrine or dopamine on hemodynamics, ventricular performance, and the interventricular relationship. RV failure was induced in 21 Danish landrace pigs by pulmonary artery banding. After 10 wk, animals were reexamined using biventricular pressure-volume conductance catheters. The maximum pressure in the RV increased by 113% (P < 0.0001) and end-diastolic volume by 43% (P < 0.002), while left ventricular (LV) pressure simultaneously decreased (P = 0.006). Concomitantly, mean arterial pressure (MAP; -16%, P = 0.01), cardiac index (CI; -23%, P < 0.0001), and mixed venous oxygen saturation (SvO2 ; -40%, P < 0.0001) decreased. Milrinone increased CI (11%, P = 0.008) and heart rate (HR; 21%, P < 0.0001). Stroke volume index (SVI) decreased (7%, P = 0.03), although RV contractility was improved. The addition of either epinephrine or dopamine further increased CI and HR in a dose-dependent manner but without any significant differences between the two interventions. A more pronounced increase in biventricular contractility was observed in the dopamine-treated animals. LV volume was reduced in both the dopamine and epinephrine groups with increasing doses In the failing pressure overloaded RV, milrinone improved CI and increased contractility. Albeit additional dose-dependent effects of both epinephrine and dopamine on CI and contractility, neither of the interventions improved SVI due to reduced filling of the LV.

194 * HEART RETRIEVAL FROM BORDERLINE PATIENTS BENEFITS FROM EARLY DONOR MANAGEMENT

Objectives: Donor heart availability is a big obstacle for heart transplant surgery. Furthermore, the pathophysiology of brain stem death, including hormonal and inflammatory changes, leads to donor organ injury. The aim of our study is to investigate whether early donor management of borderline hearts can increase the retrieval rate. Methods: Between September 2011 and February 2013, we performed early donor management for 26 potential heart donors, who were considered as borderline (on high-dose inotropes, history of hypertension and cardiopulmonary resuscitation). Our management protocol includes: inserting a pulmonary artery catheter, giving triiodothyronine, vasopressin (aiming at SVR 800-1200), methylprednisolone, and insulin. Our primary end point was donor heart acceptance depending on the results of cardiac output studies, cardiac contractility and coronary artery patency at the time of the retrieval operation. We divided the patients into two groups: group A, retrieved hearts, and group B, declined hearts. Results: We retrieved 56% (n = 14) borderline hearts after donor management (group A); all patients had good biventricular contractility and no coronary artery disease. Twelve organs were declined due to poor heart function (n = 8, P < 0.001) and coronary artery disease (n = 4, P = 0.018). The mean age of groups A and B was 42.77 and 47.78 years, respectively. Most female donors (10, 83%) were declined and only four (27%) were accepted (P = 0.005). Group A had a mean cardiac output of 6.29 l/min and group B of 3.09 l/min. Cardiopulmonary resuscitation was performed on three patients in group A and two patients in group B. One (7.1%) of the retrieved hearts (group A) and four (33.3%) of the declined hearts were from hypertensive donors. Most patients (10 [71.4%] in group A and eight [66.7%] in group B) were on noradrenaline. Conclusions: With early donor management, we were able to retrieve more than half of the potential donor hearts which were deemed unusable at the time of referral. However, we noticed a higher rate of rejection from borderline female donors. We suggest this should be adopted by all centres to increase the number of heart transplantations.

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Xenon is not superior to isoflurane on cardiovascular function during experimental acute pulmonary hypertension

Acute right ventricular afterload increase is a known perioperative challenge for the anaesthetic regime especially for patients with a compromised right ventricle. The accused negative inotropic action of volatile anaesthetics, with the exception of xenon, might be crucial for the adaptation of the right ventricle. Reversible pulmonary hypertension (mean pressure 40 mmHg) was induced by an infusion of the stable thromboxane A(2) analog U46619 in a porcine model (n = 35). The effects of 70 vol% xenon and 0.9 vol% isoflurane on biventricular function were studied by conductance catheter technique. Inflammation and myocardial injury was quantified using serum probes [tumour necrosis factor α (TNFα), interleukin 6 (IL-6), troponin] and myocardial tissue [B natriuretic peptide (BNP), TNFα, activated caspase 3] by enzyme-linked immunosorbance assays and reverse-transcription polymerase chain reaction. After wash in of xenon global haemodynamic parameters remained stable whereas isoflurane caused a systemic vasodilation. This led to a significant decrease in mean arterial pressure in the isoflurane group whereas cardiac output remained stable. Both substances did not alter the biventricular contractility nor did they induce changes in preload for both ventricles. Xenon led to an additional increase in right ventricular afterload, whereas isoflurane reduced pulmonary vascular resistance. No effects on systemic inflammatory response and myocardial injury were found, whereas higher apoptosis rate and expression of BNP and IL-6 was determined in the right ventricle. These results do not support the idea that xenon is more beneficial than isoflurane in right ventricular failure during pulmonary hypertension. Isoflurane did not compromise systolic ventricular function during acute PHT it only led to vasodilation in contrast to xenon.

348 Hearts from DCD Donors Display Excellent Biventricular Function Following Transplantation

We have previously demonstrated that resuscitation of the DCD heart is followed by metabolic and functional recovery. However, load-dependent MRI measurements suggested impairment of right ventricular contractility. Our aim was to evaluate load-independent biventricular contractility before and after DCD heart transplantation.

590 Evaluation of Load-Independent Biventricular Contractility during Machine Perfusion of the Donor Heart

Purpose: With respect to organ shortage, Non Heart Beating Donors (NHBD) are an alternative source of grafts for transplantation. In renal transplantation, machine perfusion has proven to be superior to cold storage (CS) in NHBD. Heart transplantation from NHBD is currently not performed because of the prolonged ischemia and risk of primary non-functioning. We investigated in a pig model whether machine perfusion could improve heart preservation and allow cardiac transplantation using NHBD. Methods and Materials: 16 pigs were prospectively randomised in 2 groups of NHBD. After anoxia induced cardiac arrest, hearts were harvested and preserved for 4 hours. In the first group, organs were preserved in a classical CS solution. In the second group, hearts were preserved by hypothermic machine perfusion (MP) on a modified Heartport system (Organ Recovery System; Des Plaines; IL). After preservation, the hearts were reperfused on a Langendorff system during 1 hour. Myocardial energy states (intracellular lactate, nucleotides and phosphocreatine/creatine ratio) were evaluated in myocardial biopsies taken respectively before cardiac arrest (normoxia) (1) and after 4 hours preservation (2). Results: Hearts from the MP group showed significant less lactate accumulation (4 vs 12,4 mole/g; p 0,004), lower AMP/ATP ratio (0,083 vs 0,69; p 0,049) and higher phosphocreatine/creatine ratio (33 vs 6; p 0,002) after 4 hours preservation compared to CS.

Circulating IGF‐I levels are associated with increased biventricular contractility in top‐level rowers

The intensive physical activity is often associated with cardiac changes. (i) To evaluate the IGF-I system and myocardial structure and function by standard Doppler echocardiography and Tissue Doppler in athletes and sedentary controls; and (ii) to determine any relationship between IGF-I system and echocardiographic parameters. Nineteen male top-level rowers and 19 age-matched healthy sedentary male controls underwent blood determination of fasting serum IGF-I, IGFBP-3 and acid-labile subunit levels and standard Doppler echocardiography combined with pulsed Tissue Doppler of posterior septal wall, left ventricular (LV) lateral mitral annulus and right ventricular (RV) tricuspid annulus. Myocardial presystolic (PS(m)), systolic (S(m)), the ratio of early diastolic (E(m)) to atrial (A(m)) velocities as well as myocardial time intervals were calculated. Rowers had higher serum IGF-I levels (P = 0.04), higher biventricular cavity dimensions and wall thicknesses compared to controls. They also had better LV and RV myocardial function than controls. In the rowers, IGF-I was associated with LV ejection fraction (r = 0.50, P = 0.03), RV PS(m) velocity (r = 0.55, P = 0.01) and with RV myocardial precontraction time (r = -0.57, P = 0.01). These associations remained significant after adjusting for age and heart rate. Top-level athletes showed higher IGF-I levels and a better myocardial performance than controls, particularly for the RV systolic activity. The independent correlations between IGF-I and systolic parameters of the left (ejection fraction) and right (PS(m) velocity and precontraction time) ventricles may possibly indicate a role of IGF-I system in the modulation of myocardial inotropism in athletes. Further studies are needed to confirm this hypothesis.