Continuous-flow LVADs in the Nordic countries: complications and mortality and its predictors.

OBJECTIVES: The purpose of this study was to assess complications and mortality and its predictors, with continuous-flow left ventricular assist devices (CF-LVADs) in the Nordic Countries. DESIGN: This was a retrospective, international, multicenter cohort study. RESULTS: Between 1993 and 2013, 442 surgically implanted long-term mechanical assist devices were used among 8 centers in the Nordic countries. Of those, 238 were CF-LVADs (HVAD or HeartMate II) implanted in patients >18 years with complete data. Postoperative complications and survival were compared and Cox proportion hazard regression analysis was used to identify predictors of mortality. The overall Kaplan-Meier survival rate was 75% at 1 year, 69% at 2 years and 63% at 3 years. A planned strategy of destination therapy had poorer survival compared to a strategy of bridge to transplantation or decision (2-year survival of 41% vs. 76%, p < .001). The most common complications were non-driveline infections (excluding sepsis) (44%), driveline infection (27%), need for continuous renal replacement therapy (25%) and right heart failure (24%). In a multivariate model age and left ventricular diastolic dimension was left as independent risk factors for mortality with a hazard ratio of 1.35 (95% confidence interval (CI) [1.01-1.80], p = .046) per 10 years and 0.88 (95% CI [0.72-0.99], p = .044) per 5 mm, respectively. CONCLUSION: Outcome with CF LVAD in the Nordic countries was comparable to other cohorts. Higher age and destination therapy require particularly stringent selection.

Postoperative atrial fibrillation predicts cause-specific late mortality after coronary surgery.

OBJECTIVES: To investigate the association between postoperative atrial fibrillation (POAF) and cause-specific death after coronary artery bypass grafting (CABG) over time. DESIGN: The cohort included 6821 patients undergoing primary isolated CABG between 1996 and 2009. Survival analyses using Cox proportional hazards determined the association between POAF and late mortality and cause of death. Four categories of mortality were examined: cardiac mortality; and death related to arrhythmia, cerebrovascular disease, and heart failure. RESULTS: Median follow-up was 9.8 years and 2152 of 6821 patients (32%) developed POAF. During follow-up, 2302 of 6821 patients (34%) died. For all mortality categories, lower survival rates were found among POAF patients. After adjustment for baseline characteristics, medical history, and preoperative status, POAF was related to increased mortality in all four categories: cardiac mortality (HR 1.4; 95% CI 1.3-1.5); death related to arrhythmia (HR 1.8; 95% CI 1.6-2.0); cerebrovascular disease (HR 1.4; 95% CI 1.2-1.6); and heart failure (HR 1.4; 95% CI 1.3-1.6). The effect remained more than 8 years after surgery. CONCLUSIONS: POAF predicts cause-specific late mortality after CABG, with a sustained effect many years postoperatively. This suggests that POAF-episodes are not merely an indication of more advanced disease at surgery, but predicts a persistent negative effect on cause-specific survival.

Preoperative brain natriuretic peptide predicts late mortality and functional class but not hospital readmission after cardiac surgery.

OBJECTIVES: N-terminal brain natriuretic peptide (NT-proBNP) is an established biomarker of heart failure and has been found to predict mortality and morbidity after cardiac surgery. The aim of this study was to investigate whether preoperative NT-proBNP can predict postoperative New York Heart Association (NYHA) functional class and hospital readmission in addition to morbidity and mortality. DESIGN: Retrospective. SETTING: University hospital. PARTICIPANTS: All patients undergoing aortic valve replacement for aortic stenosis and coronary artery bypass grafting from January to December 2008 (n = 390). MEASUREMENTS AND MAIN RESULTS: Preoperative NT-proBNP was recorded prospectively. Five-year mortality was obtained through national registries. Postoperative functional class, morbidity, and hospital readmission were obtained through telephone interviews. Patients were divided into quartiles based on preoperative NT-proBNP; the medians of each quartile were 103 ng/L, 291 ng/L, 825 ng/L and 2,375 ng/L. Increased preoperative NT-proBNP was associated with reduced postoperative functional class. In the first quartile, 7% (7/97) were in NYHA functional class III-IV compared to 26% (25/97) in the fourth quartile (p<0.01). Increased preoperative NT-proBNP was also associated with reduced long-term survival (p<0.01). The covariate adjusted hazard ratio for mortality in the fourth quartile was 2.9 (1.61-5.08; p<0.01) compared to the other quartiles. No association was found between preoperative NT-proBNP and postoperative hospital readmission. CONCLUSIONS: Increased preoperative NT-proBNP is associated with reduced long-term survival and functional class but not hospital readmission post-cardiac surgery. Thus, NT-proBNP might have additive value to established risk factors in the preoperative assessment of patients undergoing cardiac surgery.

Quality improvement in clinical teaching through student evaluations of rotations and feedback to departments.

BACKGROUND: Clinical teaching at medical schools needs continual improvement. We used a new evaluation instrument to gather student ratings on a departmental level across all clinical rotations. The ratings were used to enable cross comparison of departmental clinical teaching quality, official ranking and feedback as a method to improve teaching quality. This study was designed to evaluate whether these interventions increased the quality of clinical teaching. METHODS: A web-based questionnaire consisting of 10 questions (Likert scale 1-6) was introduced into all hospital departments at Uppsala University Hospital, Sweden. Specific feedback was given to participating departments based on the assessments collected. Action plans were created in order to address areas for departmental improvement. Questionnaire scores were used as a measure of clinical teaching quality. RESULTS: Mean follow-up time was 2.5 semesters. The student response rate was 70% (n = 1981). The departments' median ratings (25th-75th percentile) for the baseline were 4.05 (3.80-4.30). At follow-up, the median rating had increased to 4.56 (4.29-4.72) (p < 0.001). CONCLUSION: The introduction of a uniform clinical teaching evaluation instrument enabled cross comparison between clinical departments. Specific feedback enabled the development of action plans in the departments. This caused a rapid and substantial increase in the quality of clinical teaching.

Outcomes of aortic arch repair using the frozen elephant trunk technique: analysis of a Scandinavian center's results over 14 years.

BACKGROUND: The frozen elephant trunk (FET) technique enables repair of aortic arch pathology, with possibility for endovascular treatment of distal thoracic aortic disease. We aimed to study outcomes of FET repair of complex aortic arch disease at a Scandinavian tertiary referral center. METHODS: All patients who underwent FET repair of the aortic arch 2006-2020 were included. Survival, complication and reintervention rate, and aortic remodeling were analyzed. RESULTS: Fifty patients were included: 23 complex thoracic aortic aneurysms involving the aortic arch (TAA), 19 with chronic aortic dissections (CAD) (16 Stanford type A, 3 type B) and 8 acute aortic dissections (AAD) (7 Stanford type A, 1 type B). Thirty-day mortality was: TAA=22% (N.=5), CAD=5% (N.=1), AAD=37% (N.=3). Rate of disabling stroke: TAA=22% (N.=5), CAD=5% (N.=1), AAD=25% (N.=2). Rate of permanent spinal cord injury: TAA=9% (N.=2), CAD=5% (N.=1), AAD=0%. 5-year survival: TAA=53%, CAD=83%, AAD=63%. 5-year reintervention-free survival was TAA=83% and CAD=36%. There were no reinterventions in the AAD group. 13/19 (68%) of CAD patients underwent distal stent graft extension during follow-up. On last CT follow-up (median 32 months), 78% of CAD had false lumen thrombosis along the stent graft and 11% in the abdominal aorta. In thoracic aorta there was a mean 64% expansion (P<0.001) of true and 39% reduction (P=0.007) of false lumen diameter. In abdominal aorta, both true and false lumen expanded. CONCLUSIONS: Despite the advantages of the FET technique, repair of extensive aortic arch disease remains associated with high rates of mortality and major neurologic complications. FET repair of CAD induces favorable remodeling in the thoracic aorta.

Eligibility of extracorporeal cardiopulmonary resuscitation on in-hospital cardiac arrests in Sweden: a national registry study.

AIMS: Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest (CA) is used in selected cases. The incidence of ECPR-eligible patients is not known. The aim of this study was to identify the ECPR-eligible patients among in-hospital CAs (IHCA) in Sweden and to estimate the potential gain in survival and neurological outcome, if ECPR was to be used. METHODS AND RESULTS: Data between 1 January 2015 and 30 August 2019 were extracted from the Swedish Cardiac Arrest Register (SCAR). Two arbitrary groups were defined, based on restrictive or liberal inclusion criteria. In both groups, logistic regression was used to determine survival and cerebral performance category (CPC) for conventional cardiopulmonary resuscitation (cCPR). When ECPR was assumed to be possible, it was considered equivalent to return of spontaneous circulation, and the previous logistic regression model was applied to define outcome for comparison of conventional CPR and ECPR. The assumption in the model was a minimum of 15 min of refractory CA and 5 min of cannulation. A total of 9209 witnessed IHCA was extracted from SCAR. Depending on strictness of inclusion, an average of 32-64 patients/year remains in refractory after 20 min of cCPR, theoretically eligible for ECPR. If optimal conditions for ECPR are assumed and potential negative side effects disregarded of, the estimated potential benefit of survival of ECPR in Sweden would be 10-19 (0.09-0.19/100 000) patients/year, when a 30% success rate is expected. The benefit of ECPR on survival and CPC scoring was found to be detrimental over time and minimal at 60 min of cCPR. CONCLUSION: The number of ECPR-eligible patients among IHCA in Sweden is dependent on selection criteria and predicted to be low. There is an estimated potential benefit of ECPR, on survival and neurological outcome if initiated within 60 min of the IHCA.

Extracorporeal Cardiopulmonary Resuscitation Guided by End-Tidal Carbon Dioxide-a Porcine Model.

Extracorporeal membrane cardiopulmonary resuscitation (ECPR) during cardiopulmonary resuscitation (CPR) for selected cases and end-tidal carbon dioxide (ETCO2) could be used to guide initiation of ECPR. Ventricular fibrillation was induced in 12 pigs and CPR was performed until ETCO2 fell below 10 mmHg; then, ECPR was performed. Animals were divided into group short (GShort) and group long (GLong), according to time of CPR. Carotid blood flow was higher (p = 0.02) and mean arterial blood pressure lower in GLong during CPR (p < 0.05). B-Lactate was lower and pH higher in GShort (p < 0.01). In microdialysis lactate-pyruvate ratio, glycerol and glutamate increased in both groups during CPR, but considerably in GLong (p < 0.01). No difference could be seen in histopathology of the brain or kidney post-ECPR. No apparent histological differences of tissue damage in brains or levels of S100B in plasma were detected between groups. This might suggest that ETCO2 could be used as a marker for brain injury following ECPR.

Biological versus mechanical prosthesis in 3279 patients from the Swedish in-patients register.

OBJECTIVES: To compare valve-related morbidity among patients aged < 70 and ≥ 70 years, receiving either a mechanical or a biological prosthesis in a population-based setting. DESIGN: In total, 3279 patients (21 644 patient-years) were followed up through the Swedish National In-Patients Register, which registers all hospital admissions. Death, thromboembolism, bleeding, endocarditis, valve thrombosis and reoperations were all captured. RESULTS: Survival was lower among patients aged <70 years with a bioprosthesis compared to a mechanical prosthesis (p < 0.0001), but equal among older patients. A mechanical prosthesis indicated a lower risk (p < 0.001) of thromboembolism (1.5% per patient year, ppy), than bioprosthesis (2.6% ppy), irrespective of age. Bleeding was increased (p = 0.002) with a mechanical prosthesis (1.7% ppy) compared to a bioprosthesis (1.1% ppy); the risk of bleeding increased early (<5 years) whereas thromboembolism increased late (>5 years). Event-free survival was higher in younger patients with a mechanical prosthesis compared to bioprosthesis recipients (p < 0.001), but equal among older patients. CONCLUSIONS: Survival was comparable in older patients irrespective of prosthesis type. Bleeding was increased with a mechanical prosthesis, especially in the elderly. The risk of thromboembolism was higher in patients with a bioprosthesis.

End-Tidal Carbon Dioxide Impacts Brain and Kidney Injury in Experimental Extracorporeal Cardiopulmonary Resuscitation (ECPR).

PURPOSE: Extracorporeal membrane oxygenation-assisted cardiopulmonary resuscitation (ECPR) is proposed for cardiac resuscitation in selected cases. End-tidal carbon dioxide (ETCO2) is easily obtained during conventional cardiopulmonary resuscitation (CPR). We hypothesized that the level of ETCO2 during CPR would reflect the degree of brain and kidney damage following ECPR in experimental refractory cardiac arrest. METHODS: Ventricular fibrillation was induced in 10 pigs, followed by mechanical CPR for 45 min and thereafter ECPR for 180 min. Blood- and urine-samples, physiologic parameters, and histopathology of brain and kidney were analyzed. Animals were divided into Group High (GHigh) and Group Low (GLow) according to value of ETCO2 (10 mm Hg) at the end of CPR. RESULTS: Carotid blood pressure and blood flow declined over time in both groups during CPR but was higher in GHigh. Coefficient of determination for ETCO2 and carotid blood flow was substantial (r2 = 0.62). The oxygen delivery index was higher for GHigh 444 (396-485) L/min/m2 as compared with GLow at 343 (327-384) L/min/m2 (P = 0.02) at the end of ECPR. Also, P-S100B were lower in GHigh, (P < 0.05) and GLow demonstrated worse histopathological injury in central parts of the brain (P < 0.01). During ECPR, urinary output was higher in GHigh (P < 0.05). Kidney injury marker Plasma Neutrophil Gelatinae-associated Lipocalin increased in both groups during ECPR but was more pronounced in GLow (P = 0.03). Renal histopathology revealed no difference between groups. CONCLUSIONS: ETCO2 at the end of mechanical CPR is inversely associated with extent of brainstem and renal injury following ECPR.

Experience with the Impella recovery axial-flow system for acute heart failure at three cardiothoracic centers in Sweden.

OBJECTIVES: The Impella recovery axial-flow system is a mechanical assist system for use in acute heart failure. This retrospective study reports the use of the device at three cardiothoracic units in Sweden. DESIGN: Fifty patients (35 men, mean age 55.8 years, range 26 to 84 years) underwent implantation of 26 ImpellaLP 2.5/5.0 (support-time 0.1 to 14 days), 16 ImpellaLD (support-time 1 to 7 days) and 8 ImpellaRD (support-time 0.1 to 8 days) between 2003 and 2007. Implantation was performed because of postcardiotomy heart failure (surgical group, n=33) or for various states of heart failure in cardiological patients (non-surgical group, n=17). The intention for the treatments was mainly to use the pump as a "bridge-to-recovery". RESULTS: Early mortality in the surgical and non-surgical groups was 45% and 23%, respectively. Complications included infection, 36% and right ventricular failure, 28%. Cardiac output and cardiac power output postoperatively were significantly higher among survivors than non-survivors. CONCLUSIONS: The Impella recovery axial-flow system facilitates treatment in acute heart failure. Early intervention in patients with acute heart failure and optimized hemodynamics in the post-implantation period seem to be of importance for long-term survival. Insufficient early response to therapy should urge to consider further treatment options.

Survival after refractory cardiogenic shock is comparable in patients with Impella and veno-arterial extracorporeal membrane oxygenation when adjusted for SAVE score.

OBJECTIVES: Survival after different short-term mechanical circulatory support is difficult to compare because various systems are used and patient disease severity is most often not adjusted for. This study compares the outcome after the use of Impella and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in refractory cardiogenic shock, adjusted for disease severity through the survival after the VA-ECMO (SAVE) score. METHODS: Patients with refractory shock treated with either VA-ECMO or Impella between January 2003 and August 2015 were included. Data were analysed to assess short and long-term survival and complications. The SAVE score was calculated for the two groups and outcome was compared adjusted for the SAVE score. RESULTS: There was no difference between VA-ECMO patients (n=46) and Impella patients (n=48) in mean age or renal failure. ECMO patients were more often intubated and had lower diastolic blood pressure at device implantation. ECMO patients had a lower SAVE score (-0.4 (6.5)) compared to Impella patients (4.1 (5.4)). There was no difference in intensive care unit survival between ECMO patients 65% (52-80) or Impella patients 63% (55-79), or long-term survival between groups. When stratified into worse (III-IV) or better SAVE class (I-II) there was no difference in survival between the groups. CONCLUSIONS: Short and long-term survival is not measurably different among patients treated with Impella or VA-ECMO due to refractory cardiogenic shock, after adjustment for disease severity through the SAVE score.

High incidence of atrial fibrillation after coronary surgery.

OBJECTIVES: Postoperative atrial fibrillation (POAF) affects a third of all patients after coronary artery bypass surgery (CABG), but short-term follow-up of heart rhythm after discharge has been sporadic and shown varied results. The aim of this study was to examine the incidence of post-discharge atrial fibrillation (AF) for 30 days following hospital discharge after CABG. METHODS: A total of 67 patients, 19 (28%) with POAF during the initial hospitalization and 48 (72%) without POAF were included. Patients recorded intermittent electrocardiogram registrations three times daily, and additionally in case of arrhythmia symptoms. Presence of post-discharge AF was compared between the groups. All patients were in sinus rhythm at discharge. RESULTS: Twenty of 67 patients (30%) were diagnosed with post-discharge AF. Overall, 35% of them were entirely asymptomatic. POAF patients had a higher incidence of post-discharge AF (11 of 19, 58%) than non-POAF patients (9 of 48, 19%), with six times the odds of developing post-discharge AF compared with non-POAF patients [odds ratio (OR) 6.0; 95% CI 1.9-19, P = 0.002]. Patients with POAF registered episodes of post-discharge AF earlier during the follow-up period (mean Day 3 after discharge, range 1-9 days) than non-POAF patients (Day 10, range 7-14 days, P < 0.001). CONCLUSIONS: A high incidence of both symptomatic and asymptomatic AF was recorded during 30 days following hospital discharge after CABG. The incidence was highest among patients with POAF, of whom more than half experienced post-discharge AF.

Experimental Venoarterial Extracorporeal Membrane Oxygenation Induces Left Ventricular Dysfunction.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has experienced an increased use in acute cardiac failure. There are some reports on negative effects of VA-ECMO on cardiac function, such as left ventricular (LV) dilatation and cardiac stun, but the support in the literature is scarce. This study investigates the effects of experimental VA-ECMO on LV function in both peripheral and central cannulation. Ten pigs were randomized to VA-ECMO by either peripheral cannulation through the femoral vessels or central cannulation in the right atrium and ascending aorta. Left ventricular performance was measured with pressure-volume catheters during 5 hours of VA-ECMO. The LV end-diastolic and end-systolic volumes increased comparably in both groups during ECMO. Left ventricular ejection fraction, stroke work, and maximum rate of pressure change decreased comparably in both groups as a function of time on ECMO. The site of cannulation had no impact on the LV response to ECMO. In conclusion, VA-ECMO increased LV volumes and reduced LV function, irrespective of cannulation site in this experimental model. Reduced LV ejection fraction and stroke work indicated LV dysfunction during ECMO.

The Impella® Recover mechanical assist device in acute cardiogenic shock: a single-centre experience of 66 patients.

OBJECTIVES: Short-term ventricular assist devices are more frequently used in patients with acute cardiogenic shock. The aim of this study was to evaluate its effect on haemodynamic parameters, as well as the short- and long-term outcome and complication rate associated with the device. METHODS: All patients treated with the Impella® Recover device at our centre from 2003 to 2014 (n = 66) were included in this study, and follow-up time was 2.9 (±0.4) years. Data were obtained through patient records and the population register. Patient-related factors, preimplantation and early postimplantation haemodynamic and biochemical parameters were analysed. Characteristics of survivors and non-survivors were compared. RESULTS: The device was implanted in 66 patients and 58% (38/66) were alive at 30 days post-implantation. The mean duration of support was 7.4 (±0.8) days. Mean time in the intensive care unit was 24 (±4) days. Following device implantation, patients' cardiac index improved from 2.1 l/min/m(2) (±0.20) to 3.8 l/min/m(2) (±0.20) at Day 7, mixed venous saturation increased from 56% (±2.0) to 68% (±1.2) and diuresis increased from 69 ml/h (±9) at device insertion to 105 ml/h (±19) at Day 7 on support. Central venous pressure, lactate levels and inotropic support decreased on support. No difference between survivors and non-survivors was established. No correlation was established between preimplant parameters and 30-day mortality. CONCLUSIONS: The Impella® Recover device improved haemodynamics in patients with acute cardiogenic shock. Still, 30-day mortality remains high and future studies must focus on the optimal timing of placement of the device.

A modified Glenn shunt reduces right ventricular stroke work during left ventricular assist device therapy.

OBJECTIVES: Right ventricular (RV) failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) placement and remains hard to predict. We hypothesized that partial surgical exclusion of the RV with a modified Glenn shunt during LVAD treatment would reduce RV stroke work. METHODS: An LVAD was implanted in eight pigs and a modified Glenn shunt was constructed. A conductance pressure-volume catheter was placed in the right ventricle through the apex. Haemodynamic data and pressure-volume loops were obtained at the following time periods: (i) baseline, (ii) open shunt, (iii) LVAD with closed shunt and (iii) LVAD and open shunt. RESULTS: During LVAD therapy, the right atrial (RA) pressure increased from 9 mmHg (9-9) to 15 mmHg (12-15), P = 0.01. RV stroke volume increased from 30 ml (29-40) to 51 ml (42-53), P < 0.01. Also, RV stroke work increased to 708 mmHg ml (654-1193) from 535 mmHg ml (424-717), P = 0.04, compared with baseline. During LVAD therapy in combination with a Glenn shunt, the RA pressure decreased from 15 mmHg (12-15) to 10 mmHg (7-11) when compared with LVAD therapy only, P = 0.01. A decrease in RV stroke work from 708 mmHg ml (654-1193) to 465 mmHg ml (366-711), P = 0.04, was seen when the LVAD was combined with a shunt, not significantly different from the baseline value (535 mmHg ml). The developed pressure in the right ventricle decreased from 29 mmHg (26-32) to 21 mmHg (20-24), P < 0.01. The pressure-volume loops of the RV show a significant reduction of RV stroke work during the use of the shunt with LVAD treatment. CONCLUSIONS: A modified Glenn shunt reduced RV volumes, RV stroke work and RA pressure during LVAD therapy in an experimental model of heart failure in pigs.

Improved early results after heart valve surgery over the last decade.

OBJECTIVES: This study was undertaken to investigate time trends in early mortality, morbidity and clinical characteristics of patients undergoing heart valve surgery over the last decade. METHODS: A regional, prospectively collected, study comprising all patients (2,327) undergoing valve surgery in a defined geographical area from January 1990 to December 1999 was conducted. Data were collected from 1,746 patients submitted to aortic valve replacement (AVR), 432 to mitral valve replacement (MVR), 78 to double valve replacement (DVR) and 71 to mitral valve repairs. Logistic regression was used to identify risk factors for early mortality. Time trends of early mortality, morbidity and clinical characteristics were analysed. RESULTS: The total early mortality rate was 5.9%; for AVR it was 4.8%, MVR 9%, DVR 14% and mitral valve repair 1.4%. The risk factor profiles for early mortality were similar in all groups of valve interventions, with shock, age over 70 years and advanced NYHA class as the strongest risk factors. There was a decrease in early mortality over the period which remained after correction for risk factors. The proportion of patients over 70 years of age and of patients with diabetes increased, whereas other risk factors were not altered during the study period. CONCLUSION: It is confirmed that early risks for death after heart valve surgery have decreased. This improvement was consistent after adjustment for risk factors.

A modified Glenn shunt reduces venous congestion during acute right ventricular failure due to pulmonary banding: a randomized experimental study.

OBJECTIVES: Right ventricular failure after left ventricular assist device implantation is a serious complication with high rates of mortality and morbidity. It has been demonstrated in experimental settings that volume exclusion of the right ventricle with a modified Glenn shunt can improve haemodynamics during ischaemic right ventricular failure. However, the concept of a modified Glenn shunt is dependent on a normal pulmonary vascular resistance, which can limit its use in some patients. The aim of this study was to explore the effects of volume exclusion with a modified Glenn shunt during right ventricular failure due to pulmonary banding, and to study the alterations in genetic expression in the right ventricle due to pressure and volume overload. METHODS: Experimental right ventricular failure was induced in pigs (n = 11) through 2 h of pulmonary banding. The pigs were randomized to either treatment with a modified Glenn shunt and pulmonary banding (n = 6) or solely pulmonary banding (n = 5) as a control group. Haemodynamic measurements, blood samples and right ventricular biopsies for genetic analysis were sampled at baseline, at right ventricular failure (i.e. 2 h of pulmonary banding) and 1 h post-right ventricular failure in both groups. RESULTS: Right atrial pressure increased from 10 mmHg (9.0-12) to 18 mmHg (16-22) (P < 0.01) and the right ventricular pressure from 31 mmHg (26-35) to 57 mmHg (49-61) (P < 0.01) after pulmonary banding. Subsequent treatment with the modified Glenn shunt resulted in a decrease in right atrial pressure to 13 mmHg (11-14) (P = 0.03). In the control group, right atrial pressure was unchanged at 19 mmHg (16-20) (P = 0.18). At right heart failure, there was an up-regulation of genes associated with heart failure, inflammation, angiogenesis, negative regulation of cell death and proliferation. CONCLUSIONS: Volume exclusion with a modified Glenn shunt during right ventricular failure reduced venous congestion compared with the control group. The state of right heart failure was verified through genetic expressional changes.

Cavoaortic shunt improves hemodynamics with preserved oxygen delivery in experimental right ventricular failure during left ventricular assist device therapy.

OBJECTIVE: Right heart failure is a major cause of morbidity and mortality after left ventricular assist device (LVAD) implantation. This study evaluated the approach of a cavoaortic shunt included in the LVAD circuit, which would aim to relieve venous congestion and improve hemodynamics with preserved oxygen delivery during induced right ventricular failure. METHODS: Right ventricular failure was induced by coronary ligation in 10 pigs. An LVAD was implanted and a cavoaortic shunt was created from the right atrium and included in the assist circuit. Hemodynamic measures and blood gas analyses were analyzed. Oxygen delivery and oxygen consumption were estimated. RESULTS: Right atrial pressure decreased from more than 20 mm Hg to 17.2 mm Hg (14.8-18.4) with the LVAD and to 14.1 mm Hg (11.2-15.5) (P < .01) with the LVAD and cavoaortic shunt. Mean arterial pressure increased from 70.9 mm Hg (67.6-79.8) to 81.5 mm Hg (70.8-92.6) (P = .02) with addition of the shunt into the assist circuit. Cardiac output increased from 3.5 L/min (2.6-4.2) to 4.9 L/min (3.5-5.6) (P < .01) with cavoaortic shunting. Oxygen delivery with the cavoaortic shunt was 337 mL/min (± 70) as compared with left ventricular assist alone at 258 mL/min (± 52) (P < .01). Oxygen consumption was restored during use of the cavoaortic shunt. CONCLUSIONS: A cavoaortic shunt combined with an LVAD during right ventricular failure reduces central venous pressures, increases systemic arterial pressure, and enables increased cardiac output compared with device therapy alone. This was feasible with preserved oxygen delivery.

A modified Glenn shunt improves haemodynamics in acute right ventricular failure in an experimental model.

OBJECTIVES: Right heart failure is a major cause of morbidity and mortality after left ventricular assist device implantation and is still hard to predict. This study investigated the haemodynamic effect of a modified Glenn shunt on induced right ventricular (RV) failure. METHODS: Isolated RV failure was induced by coronary ligation in 11 pigs. A modified Glenn shunt was established by a superior vena cava to pulmonary artery connection. Haemodynamic data were obtained at baseline, RV failure, and RV failure and open shunt. Myocardial biopsies were taken to ascertain established heart failure. RESULTS: RV failure defined as right atrial pressure ≥20 mmHg was achieved in all 11 animals. A reduction in cardiac output (CO) from 3.7 (3.5-4.2) to 2.3 l/min (2.0-2.6) and mean arterial pressure (MAP) from median 72.7 (70.1-82.2) to 55.9 mmHg (52.6-59.8) was seen during heart failure. The median flow in the shunt was 681 ml. Right atrial pressures decreased from 20.3 (19.6-21.1) to 13.4 mmHg (12.7-14.0), and RV pressures decreased from 18.1 (16.4-20.1) to 13.6 mmHg (13.5-14.2) with open shunt (P = 0.001 for both). CO increased to 2.9 l/min (2.4-3.3) when the shunt was in use. Mixed venous oxygen saturation increased with the shunt from 32 (27-38) to 49% (45-56), P = 0.001. Genes associated with heart failure were upregulated during heart failure. CONCLUSIONS: A modified Glenn shunt improved haemodynamics by reduced right atrial pressure, increased CO, MAP and mixed venous oxygen saturation in an experimental model of induced RV failure.

Percutaneous left-ventricular support with the Impella-2.5-assist device in acute cardiogenic shock: results of the Impella-EUROSHOCK-registry.

BACKGROUND: Acute cardiogenic shock after myocardial infarction is associated with high in-hospital mortality attributable to persisting low-cardiac output. The Impella-EUROSHOCK-registry evaluates the safety and efficacy of the Impella-2.5-percutaneous left-ventricular assist device in patients with cardiogenic shock after acute myocardial infarction. METHODS AND RESULTS: This multicenter registry retrospectively included 120 patients (63.6±12.2 years; 81.7% male) with cardiogenic shock from acute myocardial infarction receiving temporary circulatory support with the Impella-2.5-percutaneous left-ventricular assist device. The primary end point evaluated mortality at 30 days. The secondary end point analyzed the change of plasma lactate after the institution of hemodynamic support, and the rate of early major adverse cardiac and cerebrovascular events as well as long-term survival. Thirty-day mortality was 64.2% in the study population. After Impella-2.5-percutaneous left-ventricular assist device implantation, lactate levels decreased from 5.8±5.0 mmol/L to 4.7±5.4 mmol/L (P=0.28) and 2.5±2.6 mmol/L (P=0.023) at 24 and 48 hours, respectively. Early major adverse cardiac and cerebrovascular events were reported in 18 (15%) patients. Major bleeding at the vascular access site, hemolysis, and pericardial tamponade occurred in 34 (28.6%), 9 (7.5%), and 2 (1.7%) patients, respectively. The parameters of age >65 and lactate level >3.8 mmol/L at admission were identified as predictors of 30-day mortality. After 317±526 days of follow-up, survival was 28.3%. CONCLUSIONS: In patients with acute cardiogenic shock from acute myocardial infarction, Impella 2.5-treatment is feasible and results in a reduction of lactate levels, suggesting improved organ perfusion. However, 30-day mortality remains high in these patients. This likely reflects the last-resort character of Impella-2.5-application in selected patients with a poor hemodynamic profile and a greater imminent risk of death. Carefully conducted randomized controlled trials are necessary to evaluate the efficacy of Impella-2.5-support in this high-risk patient group.