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.

Severe chronic aortic regurgitation after percutaneous coronary intervention: a case report and literature review.

BACKGROUND: Severe aortic regurgitation (AR) is an extremely rare complication after coronary catheterization and percutaneous coronary intervention (PCI), where most reported cases have required relatively urgent surgical intervention due to acute-onset AR and cardiac decompensation. CASE SUMMARY: We report a case of a 60-year-old woman that previously presented with a non-ST-elevation myocardial infarction (NSTEMI) due to an ostial right coronary artery stenosis. During the course of 2 years, she developed five recurrent NSTEMI due to in-stent thrombosis, necessitating either a new coronary stent or balloon. She developed a chronic severe AR due to a drug-eluting coronary stent protruding from the right coronary artery and underwent successful aortic valve replacement and coronary artery by-pass grafting. DISCUSSION: We performed a literature review and identified 16 reported cases of iatrogenic severe aortic regurgitation related to coronary catheterization or percutaneous coronary intervention. All patients developed an acute aortic regurgitation and, thus, we report the first case of a delayed complication caused by a protruding coronary stent. The surgical strategy is related to the extent of the damage, where smaller perforations or lacerations seems to be feasible for aortic valve repair and larger defects more often lead to aortic valve replacement. Our patient developed a fibrotic right coronary cusp which could not be used to perform a successful aortic valve repair.

Technical eligibility for endovascular treatment of the aortic arch after open type A aortic dissection repair.

OBJECTIVE: The objective was to report on the technical eligibility of patients previously treated for Stanford type A aorta dissection for endovascular aortic arch repair based on contemporary anatomic criteria for an arch inner-branched stent graft. METHODS: All patients treated for type A aorta dissection from 2004 to 2015 at a single aortic center were identified. Extent of repair and use of circulatory arrest were reported. Survival and reoperation were assessed using Kaplan-Meier and competing risk models. Anatomic assessment was performed using 3-dimensional computed tomography imaging software. Primary outcome was survival of 1 year or more and fulfillment of the arch inner-branched stent graft anatomic criteria. RESULTS: A total of 198 patients were included (158 DeBakey I, 32 DeBakey II, and 8 intramural hematoma). Mortality was 30 days (16.2%), 1 year (16.3%), and 10 years (45.0%). A total of 129 patients had imaging beyond 1 year (mean, 47.8 months), and 89 patients (69.0%) were eligible for arch inner-branched stent grafting. During follow-up, 19 patients (14.7%) met the threshold criteria for aortic arch treatment, of whom 14 (73.7%) would be considered eligible for arch inner-branched stent graft. Patients who underwent type A aorta dissection repair with circulatory arrest and no distal clamp were more often eligible for endovascular repair (88.8%) than those operated with a distal clamp (72.5%; P = .021). Among patients who did not meet the arch inner-branched stent graft anatomic criteria, the primary reasons were mechanical valve (40%) and insufficient proximal seal (30%). CONCLUSIONS: More than two-thirds of patients post-type A aorta dissection repair are technically eligible for endovascular arch inner-branched stent graft repair. The development of devices that can accommodate a mechanical aortic valve and a greater awareness of sufficient graft length would significantly increase availability.

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.

Long-term survival and frequency of reinterventions after proximal aortic surgery: a retrospective study†.

OBJECTIVES: We sought to analyse perioperative outcome, long-term mortality, frequency and causes of reintervention, and survival benefit in a contemporary cohort of patients undergoing proximal thoracic aortic surgery. METHODS: Participants comprised all patients undergoing open surgery for proximal thoracic aortic aneurysm (TAA) (n = 319) and thoracic aortic dissection type A (TAD) (n = 229) during 2005-2014 at the Department of Thoracic Surgery, Uppsala University Hospital. Long-term survival was compared to age- and sex-matched controls. Perioperative mortality and morbidity, event-free survival and causes of reoperation were also analysed. RESULTS: Long-term mortality was normalized in patients with TAA, and a survival benefit was seen as early as 20 months when corrected for time lost due to perioperative mortality. Long-term survivors undergoing surgery for TAD, on the other hand, had a 10-year mortality of 130% [95% confidence interval (95% CI) 120-140%] compared to age- and sex-matched controls. Moreover, their event-free survival was half that of patients with TAA (hazard ratio 2.3; 95% CI 1.7-3.2). Reintervention (i.e. reoperation or thoracic endovascular aortic repair) was also twice as common in the TAD patients (odds ratio 2.0; 95% CI 1.1-3.5). The dominant causes for reoperation among TAD patients were aortic insufficiency, aortic arch aneurysm and infection. CONCLUSIONS: Surgery for TAA is relatively safe, normalizes long-term mortality and confers an early survival benefit. However, TAD surgery carries a high risk of perioperative mortality and morbidity, as well as increased long-term mortality and risk of reintervention.

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.

Validity of the Swedish Cardiac Surgery Registry.

OBJECTIVES: Our goal was to validate the Swedish Cardiac Surgery Registry by reviewing the reported cardiac operations to assess the completeness and quality of the registered data and the EuroSCORE II variables. METHODS: A total of 5837 cardiac operations were reported to the Swedish Cardiac Surgery Registry in Sweden during 2015. A randomly selected sample of 753 patient records (13%) was scrutinized by 3 surgeons at all 8 units in Sweden performing open cardiac surgery in adults. RESULTS: Coverage was excellent with 99% [95% confidence interval (CI) 98-99%] of the performed procedures found in the registry. Reported waiting times for surgery were correct in 78% (95% CI 76-79%) of the cases. The main procedural code was correctly reported in 96% (95% CI 95-97%) of the cases. The correlation between reported and monitored logistic EuroSCORE II had a coefficient of 0.79 (95% CI 0.76-0.82), and the median difference in EuroSCORE II was 0% (interquartile range -0.4% to 0.4%). The majority of EuroSCORE II variables had good agreement and coherence; however, New York Heart Association functional class, preoperative renal dysfunction, left ventricular ejection fraction, Canadian Cardiovascular Society Class IV angina and poor mobility were less robust. Postoperative complications were rare and in general had a high degree of completeness and agreement. CONCLUSIONS: The reliability of the variables in the national Swedish Cardiac Surgery Registry was excellent. Thus, the registry is a valuable source of data for quality studies and research. Some EuroSCORE II variables require improved and stricter definitions to obtain uniform reporting and high validity.

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.

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.

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.