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Vein of Galen malformation (VGM) is a rare intracranial vascular malformation. High output heart failure is common in infancy and is characterized by dilatation of all the cardiac chambers. We report an unusual case of VGM in a 3-month-old infant without dilatation of the right-sided cardiac chambers. We then demonstrate importance of comprehensive evaluation in detecting rare coexistence of anomalous right superior caval vein connection to the left atrium.

Objective: Flow reduction is required to preserve vascular access in cases with high flow access (HFA). We report a new flow reduction procedure, the graft inclusion technique (GIT). Methods: The GIT procedure developed by us involves the intraluminal placement and suturing of a 4-mm polytetrafluoroethylene graft to the anastomosis and outflow tract to plicate the enlarged anastomosis and maintain lower flow volumes. Flow reduction for HFA was retrospectively assessed in a series of 25 patients (age 65±12 years; 17 males and 8 females) to evaluate flow volume and patency rate, wherein 10 patients underwent conventional methods of flow reduction and 15 underwent GIT. Results: Compared with preprocedure values, mean flow volume (MFV) was significantly lower after the procedure with both the conventional methods (1,817 vs. 586 ml/min; P

Graphical abstract, Highlights • Arteriovenous fistula for hemodialysis occasionally causes heart failure. • Noninvasive assessment of arteriovenous fistula hemodynamics is not established. • Refractory heart failure developed in a patient with an arteriovenous fistula. • Echocardiography can monitor hemodynamics, directing arteriovenous fistula occlusion.

Background: Several risk factors including Ischemic heart disease, uncontrolled hypertension, high output Heart Failure (HF) from shunting through vascular hemodialysis access, and anemia, contribute to development of HF in patients with End-Stage Renal Disease (ESRD). Guideline-directed medical and device therapy for Heart Failure with Reduced Ejection Fraction (HFrEF) has not been extensively studied and may have limited safety and efficacy in patients with ESRD. Results: Maintenance of interdialytic and intradialytic euvolemia is a key component of HF management in these patients but often difficult to achieve. Beta-blockers, especially carvedilol which is poorly dialyzed is associated with cardiovascular benefit in this population. Despite paucity of data, Angiotensin-converting Enzyme Inhibitors (ACEI) or Angiotensin II Receptor Blockers (ARBs) when appropriately adjusted by dose and with close monitoring of serum potassium can also be administered to these patients who tolerate beta-blockers. Mineralocorticoid receptors in patients with HFrEF and ESRD have been shown to reduce mortality in a large randomized controlled trial without any significantly increased risk of hyperkalemia. Implantable Cardiac-defibrillators (ICDs) should be considered for primary prevention of sudden cardiac death in patients with HFrEF and ESRD who meet the implant indications. Furthermore in anemic iron-deficient patients, intravenous iron infusion may improve functional status. Finally, mechanical circulatory support with left-ventricular assist devices may be related to increased mortality risk and the presence of ESRD poses a relative contraindication to further evaluation of these devices.

Enhanced carotid body (CB) chemoreflex function is strongly related to cardiorespiratory disorders and disease progression in heart failure (HF). The mechanisms underlying CB sensitization during HF are not fully understood, however previous work indicates blood flow per se can affect CB function. Then, we hypothesized that the CB-mediated chemoreflex drive will be enhanced only in low output HF but not in high output HF. Myocardial infarcted rats and aorto-caval fistulated rats were used as a low output HF model (MI-CHF) and as a high output HF model (AV-CHF), respectively. Blood flow supply to the CB region was decreased only in MI-CHF rats compared to Sham and AV-CHF rats. MI-CHF rats exhibited a significantly enhanced hypoxic ventilatory response compared to AV-CHF rats. However, apnea/hypopnea incidence was similarly increased in both MI-CHF and AV-CHF rats compared to control. Kruppel-like factor 2 expression, a flow sensitive transcription factor, was reduced in the CBs of MI-CHF rats but not in AV-CHF rats. Our results indicate that in the setting of HF, potentiation of the CB chemoreflex is strongly associated with a reduction in cardiac output and may not be related to other pathophysiological consequences of HF.

Activin like kinase-1 (AlK-1) mediates signaling via the transforming growth factor beta (TGFβ) family of ligands. AlK-1 activity promotes endothelial proliferation and migration. Reduced AlK-1 activity is associated with arteriovenous malformations. No studies have examined the effect of global AlK-1 deletion on indices of cardiac remodeling. We hypothesized that reduced levels of AlK-1 promote maladaptive cardiac remodeling. To test this hypothesis, we employed AlK-1 conditional knockout mice (cKO) harboring the ROSA26-CreER knock-in allele, whereby a single dose of intraperitoneal tamoxifen triggered ubiquitous Cre recombinase-mediated excision of floxed AlK-1 alleles. Tamoxifen treated wild-type (WT-TAM; n = 5) and vehicle treated AlK-1-cKO mice (cKO-CON; n = 5) served as controls for tamoxifen treated AlK-1-cKO mice (cKO-TAM; n = 15). AlK-1 cKO-TAM mice demonstrated reduced 14-day survival compared to cKO-CON controls (13 vs 100%, respectively, p

Aortocaval fistulas are a rare cause of high output heart failure. The infrequency with which it is encountered makes these fistulas a formidable diagnostic and treatment challenge. In the absence of infection, traditional repair with open surgical approach has required in-situ graft replacement of the affected portion of the aorta with concomitant repair of the cava defect. Mortality associated with open repair is reported to be as high as 66%. Technical advances in endovascular treatment of aortic aneurysms over the past two decades are increasingly used in other large vessel pathologies. This mini-review summarizes current evidence for employing endovascular techniques for aortocaval fistulas.

Background Arteriovenous malformations rarely cause congestive heart failure. Pregnancy may in theory trigger heart failure associated with congenital arteriovenous malformations leading to secondary pulmonary hypertension, but no cases have been reported proving that condition. Methods and results We report a 23-year-old pregnant woman at 36 + 5 weeks of gestation requiring urgent medical care because of shortness of breath. High-output heart failure was suspected, and a congenital arteriovenous malformation on the right scapular region was considered as the possible origin. The patient required urgent caesarean delivery because of ongoing cardiac failure, which improved soon after delivery. Postpartum angiography of the right subclavian artery revealed an arteriovenous malformation on the deltoid region with venous drainage through the subclavian vein and increased flow to the superior cava vein and right atrium. Conclusion A high index of suspicion of arteriovenous malformations should be maintained in pregnant women with cutaneous vascular malformation-like lesions, if symptoms of heart failure are present.

Author(s): Srivastava, Pratyaksh K; Vyas, Nina; Jones, Jesse; Wong, Thalia C; Holliman, Kerry; Small, Adam J; Rao, Rashmi R; Dowling, Erin P; Finn, J Paul; Duckwiler, Gary R; Reardon, Leigh C; Aboulhosn, Jamil A; Ascher, Simon B; Hogeling, Marcia; Lluri, Gentian; Yang, Eric H

Background Endoglin is a co-receptor for TGFbeta/BMP9/10 signalling and ENG mutations lead to the vascular disorder hereditary haemorrhagic telangiectasia type I (HHT). Endoglin is also required for normal vascular development and angiogenesis, but little is known about endoglin's role in quiescent adult vascular endothelium. Purpose The goal of this present study is to determine how endoglin maintains vessel calibre in adult life to prevent AVM formation and thereby protect heart function. Methods To investigate this role, tamoxifen was administered to adult Cdh5(PAC)-CreERT2; Engfl/fl mice to generate endothelial-specific depletion of endoglin (Eng-iKOe). Cardiac magnetic resonance imaging, myography, vascular casting, microsphere injection, immunohistology, qPCR and aortic telemetry were used to evaluate cardiovascular changes after endoglin knockdown. Results Endothelial-specific loss of endoglin leads to an enlarged heart and cardiomyocyte hypertrophy within 5 weeks, progressing to high output heart failure (HOHF). In vivo aortic telemetry revealed significant loss of aortic pressure within a few days of endoglin depletion. Increased cardiac size and reduced cardiac afterload were confirmed by ventricular pressure loop analysis. As HOHF could result from arteriovenous malformations (AVMs), and these are found primarily in mucocutaneous and pulmonary tissues in HHT, we systematically screened for AVMs using microspheres and vascular casting. Although AVMs were absent in the majority of tissues, they were observed in the pelvic region and may account for the rapid increase in cardiac output. The pelvic cartilaginous symphysis is a noncapsulated cartilage with a naturally high endogenous expression of vascular endothelial growth factor (VEGF). Development of pelvic AVMs in this region of high VEGF expression occurred because loss of endoglin in endothelial cells leads to increased sensitivity to VEGF and a hyper-proliferative response. Finally, we found that inhibition of VEGFR2 was protective against AVMs development, enlargement of the heart and dilatation of the ventricles. Conclusion Our results showed the essential role of endoglin in the maintenance of adult cardio-vasculature through crosstalk with the VEGF signalling pathway. Acknowledgement/Funding British Heart Foundation, Cure HHT, The Swedish Research Council, The Cardiovascular Programme at Karolinska Institutet, The Swedish Cancer Society

Patients with iatrogenic iliac arteriovenous fistulas (IAVFs) after lumbar discectomy surgeries (LDSs) from our hospital and the published literature were reviewed in order to better understand this clinical phenomenon. Literature from databases about iatrogenic IAVFs after LDSs were retrieved and a patient from our hospital was reviewed with emphasis placed upon the patient's clinical data. From 31 publications and studies of 44 individuals' data, the study revealed L4-L5 and/or L5-S1 intervertebral space levels were mostly involved (62.0%). Most of the patients underwent computed tomography angiography (CTA) and/or digital subtraction angiography (DSA) examinations to confirm the potential diagnosis and rule out other differential diagnosis (86.4%). Most of the patients (63.6%) developed features of high output heart failure months to years after the LDSs, and the majority of them (88.6%) were treated with endovascular repairs. An iatrogenic IAVF after an LDS is a rare occurrence; however, more attention should be paid to it for the purpose of obtaining accurate diagnosis and proper treatment.

Hereditary haemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder resulting in uncontrolled multisystem angiogenesis. The pathogenesis of this disease is thought to relate to elevated levels of transforming growth factor beta and vascular endothelial growth factor (VEGF). The frail arteriovenous malformations (AVMs) give rise to complications including haemorrhage and shunting. These have classically included recurrent epistaxis and gastrointestinal bleeding and associated iron-deficiency anaemia. More recently, high-output heart failure has been recognized in patients with significant hepatic involvement. This is thought to occur as a result of low systemic resistance due to shunting of blood through liver AVMs with an associated compensatory increase in cardiac output. Bevacizumab is a humanized monoclonal that acts to cause VEGF inhibition. Previously, this drug has been shown to benefit patients with HHT by reducing transfusion requirements and frequency of epistaxis. In addition, there is a growing body of evidence that bevacizumab may be associated with amelioration of high-output cardiac failure associated with HHT-induced hepatic shunting. We believe this case supports the use of bevacizumab in this context.

Introduction The differential for cardiomyopathy in a young patient is challenging. While there has been published research into genetic cardiomyopathy and lymphocytic myocarditis, there is still much to be studied. Case Report A 27 year old male with significant family history of heart disease and no drug/steroid use, initially presented following cardiac arrest while exercising. Patient was found to be apneic and pulseless upon arrival of EMS. ACLS was performed. In the ED, he was found to have an EF of 10% and global hypokinesis. Lab work showed an elevated troponin which peaked at 20. Angiogram showed no significant obstructions. Patient developed evidence of cardiogenic shock, ultimately requiring pressors, IABP, and VA ECMO. Genetic testing was obtained which showed variance in FLNC and RBM40. Cardiac MRI demonstrated no late gadolinium enhancement. Right heart catherization and myocardial biopsy demonstrated evidence of high output heart failure and borderline lymphocytic myocarditis. Repeat ECHO demonstrated an improved ejection fraction of 43%. Patient was later decannulated and IABP was removed. Patient ultimately underwent AICD placement, and later interrogation noted episodes of VTach of unclear etiology. Patient was optimized on beta blockers, ARNI, and antiarrhythmics. Ejection fraction one year after admission remained 43%. Summary This case highlights the differential for cardiomyopathy in a 27 year old. While the diagnosis at this time is unclear, two main diagnoses become prominent: lymphocytic myocarditis versus underlying genetic disorder. Lymphocytic myocarditis accounts for 54% of all myocarditis, with viral illness the most common identified cause. Workup includes exclusion of other etiologies, as well as endomyocardial biopsy. While the role of medical therapy, such as immunosuppression or antivirals is unclear, the most effective treatment is supportive care. Genetic cardiomyopathies, however are more insidious. While there is still much to know about genetic cardiomyopathies, there have been advances in the recognition of genetic mutations that lead to earlier recognition and treatment. Also, patients with underlying genetic cardiomyopathies can be predisposed to lymphocytic myocarditis. This case is interesting in that it allows us to explore the differential for cardiomyopathy in a young healthy patient, and how the field of cardiomyopathy is evolving.

Morbid obesity remains most common cause of high output failure. The prevalence of the obesity is growing when two-thirds of American adults already are overweight or obese. Obesity is the risk factor for heart disease and eventually leads to heart failure. High output heart failure is common in obese patients and is characterized by high cardiac output, decreased systemic vascular resistance, and increased oxygen consumption. It often occurs in patients with chronic severe anemia, hyperthyroidism, pregnancy, arterial-venous fistulas, and liver disease. However, the pathogenesis of obesity-related high output heart failure is not fully understood. The clinical management of obesity-related high output heart failure follows conventional heart failure regimens due to lack of specific clinical recommendations. This article reviews the possible pathophysiological mechanisms and causes that contribute to obesity-related high output heart failure. This review also focuses on the implications for clinical practice and future research involved with omics technologies to explore possible molecular pathways associated with obesity-related high output heart failure.

Background & Aims Hereditary haemorrhagic telangiectasia is characterized by arterio-venous malformations (AVM). It frequently involves the liver without clinical symptoms, but may lead to biliary ischaemia, portal hypertension, or fatal high-output heart failure. The indication of liver transplantation is controversial. Methods Herein, we report the case of a 65-year-old female patient with a ‘double Osler syndrome’ consisting of hereditary haemorrhagic telangiectasia (HHT) and type I hereditary angioedema diagnosed at the age of 25 and 22 years respectively. Results Hereditary angioedema was treated with danazol for several decades until multiple hypoechogenic liver masses were detected. Albeit danazol treatment was replaced by C1 esterase inhibitor infusions, hepatocellular carcinoma was diagnosed at the age of 64 and the patient was listed for liver transplantation. HHT was marked by recurrent epistaxis until the age of 63 when severe intestinal bleeding occurred. At the age of 65, severe dyspnoea (NYHA class IV) developed and rapidly progressive high-output cardiac failure was diagnosed. Despite argon plasma coagulation to control bleeding from intestinal angiodysplasia, and treatment with bevacizumab to inhibit angiogenesis, the patient died from severe gastrointestinal bleeding associated with cardiogenic shock at the age of 66 before being transplanted. Conclusion The indication to list this patient for liver transplantation was debated several times before the diagnosis of hepatocellular carcinoma because of good general condition and low MELD score. Precise guidelines for screening and management of patients with hepatic HHT need to be better defined.

Background High-output heart failure (HF) is an unusual cause of cardiac failure that has not been well-characterized. Objectives This study sought to characterize the etiologies, pathophysiology, clinical and hemodynamic characteristics, and outcomes of high-output HF in the modern era. Methods We performed a retrospective analysis of all consecutive patients referred to the Mayo Clinic catheterization laboratory for hemodynamic assessment between 2000 and 2014. Subjects with definite HF, as defined by the Framingham criteria, were compared to controls of similar age and sex. Results The most common etiologies of high-output HF (n = 120) were obesity (31%), liver disease (23%), arteriovenous shunts (23%), lung disease (16%), and myeloproliferative disorders (8%). Compared with controls (n = 24), subjects with high-output HF displayed eccentric left ventricular remodeling, greater natriuretic peptide activation, higher filling pressures, pulmonary hypertension, and increased cardiac output, despite similar ejection fraction. Elevated cardiac output in high-output HF patients was related to both lower arterial afterload (decreased systemic vascular resistance) and higher metabolic rate. Mortality was increased in high-output HF as compared with controls (hazard ratio: 3.4; 95% confidence interval: 1.6 to 7.6). Hemodynamics and outcomes were poorest amongst patients with the lowest systemic vascular resistance. Conclusions High-output HF is an important cause of clinical HF in the modern era that is related to excessive vasodilation, and most frequently caused by obesity, arteriovenous shunts, and liver disease. Given the high mortality and increasing prevalence of these comorbidities in Western countries, high-output HF must be considered in the differential diagnosis of patients presenting with dyspnea, congestion, and a normal ejection fraction.

BACKGROUND Satisfactory vascular access flow (Qa) of an arteriovenous fistula (AVF) is necessary for haemodialysis (HD) adequacy. The aim of the present study was to further our understanding of haemodynamic modifications of the cardiovascular system of HD patients associated with an AVF. The main objective was to calculate using real data in what way an AVF influences the load of the left ventricle (LLV). METHODS All HD patients treated in our dialysis unit and bearing an AVF were enrolled into the present observational cross-sectional study. Fifty-six patients bore a lower arm AVF and 30 an upper arm AVF. Qa and cardiac output (CO) were measured by means of the ultrasound dilution Transonic Hemodialysis Monitor HD02. Mean arterial pressure (MAP) was calculated; total peripheral vascular resistance (TPVR) was calculated as MAP/CO; resistance of AVF (AR) and systemic vascular resistance (SVR) are connected in parallel and were respectively calculated as AR = MAP/Qa and SVR = MAP/(CO - Qa). LLV was calculated on the principle of a simple physical model: LLV (watt) = TPVR·CO(2). The latter was computationally divided into the part spent to run Qa through the AVF (LLVAVF) and that part ensuring the flow (CO - Qa) through the vascular system. The data from the 86 AVFs were analysed by categorizing them into lower and upper arm AVFs. RESULTS Mean Qa, CO, MAP, TPVR, LLV and LLVAVF of the 86 AVFs were, respectively, 1.3 (0.6 SD) L/min, 6.3 (1.3) L/min, 92.7 (13.9) mmHg, 14.9 (3.9) mmHg·min/L, 1.3 (0.6) watt and 19.7 (3.1)% of LLV. A statistically significant increase of Qa, CO, LLV and LLVAVF and a statistically significant decrease of TPVR, AR and SVR of upper arm AVFs compared with lower arm AVFs was shown. A third-order polynomial regression model best fitted the relationship between Qa and LLV for the entire cohort (R (2) = 0.546; P < 0.0001) and for both lower (R (2) = 0.181; P < 0.01) and upper arm AVFs (R (2) = 0.663; P < 0.0001). LLVAVF calculated as % of LLV rose with increasing Qa according to a quadratic polynomial regression model, but only in lower arm AVFs. On the contrary, no statistically significant relationship was found between the two parameters in upper arm AVFs, even if mean LLVAVF was statistically significantly higher in upper arm AVFs (P < 0.0001). CONCLUSIONS Our observational cross-sectional study describes statistically significant haemodynamic modifications of the CV system associated to an AVF. Moreover, a quadratic polynomial regression model best fits the relationship between LLVAVF and Qa, but only in lower arm AVFs.

Introduction Acute injury to the large vessels is the most feared of diagnoses for a spinal surgeon, but far more common is the delayed presentation of arteriovenous fistula (AVF) formation. The mean time to diagnosis of an AV fistula in this scenario is just over 1 month. Treatment can include both open and endovascular repair. Report This study presents a case of an otherwise healthy 39-year-old woman who initially presented with orthopnea, leg edema, and a presumptive diagnosis of post-partum cardiomyopathy. Cardiac investigations revealed high output cardiac failure and an abdominal CT scan confirmed an arterial venous fistula from the left common iliac artery to left common iliac vein. The patient maintained a cardiac output three times normal prior to her definitive treatment. This high flow physiology caused unique challenges for the endovascular procedure as the stent graft collapsed and distorted toward the iliac side wall. The AV fistula was eventually covered successfully and post-operative studies show no further fistula and normal cardiac function. This case demonstrates an unanticipated effect of very high flows of stent graft deployment. Discussion Extreme high flow AV fistulas can present as unexpected challenges to endovascular repair. These issues may be ameliorated by techniques such as controlled hypotension, adenosine, ventricular pacing, or proximal balloon occlusion., Highlights • This chronic AV fistula was diagnosed 12 years after lumbar discectomy. • Only after the normal physiological state of pregnancy, and its elevated high cardiac output requirements did the patient decompensate with orthopnea and edema. • This otherwise healthy 39-year-old woman had three times the cardiac output expected which was caused by her iliac artery to iliac vein fistula. • Endovascular treatment is a viable option to cover the fistula, but the high flows can collapse and distort the stent graft during deployment. • Controlled hypotension, adenosine, ventricular pacing or proximal balloon occlusion may be appropriate if extreme flows are anticipated.

Aorto-pulmonary fistula is an infrequent but often fatal condition resulting as a late complication of an aortic aneurysm. The most common cause is erosion of a false aneurysm of the aortic arch into the pulmonary artery, resulting in the development of a left-to-right shunt and leading to acute pulmonary edema and right heart failure. We report our experience with aorto-pulmonary fistula as a rare complication associated with thoracic aortic aneurysm and high output heart failure.

Recently, the zebrafish has gained attention as an innovative experimental model to decipher molecular and cellular mechanisms involved in cardiovascular development and diseases. Nevertheless, the use of zebrafish models has been challenged because the transparency of these fish, which allows for accurate cardiac evaluation, disappears in adulthood. In this study, the epicardial outline method was performed to investigate the feasibility of echocardiography in assessing cardiac function in pathological adult zebrafish.We attempted to estimate heart failure in adult zebrafish treated with three distinct regulators of cardiac function: phenylhydrazine hydrochloride (PHZ), doxorubicin (DOX), and ethanol. B-mode and Doppler images were evaluated at frequencies of up to 50 MHz and 40 MHz, respectively. The correlation between alterations in cardiac function, haemoglobin concentration, and myocardial histopathology were assessed.Cardiac output (CO) in PHZ-treated zebrafish was significantly higher than that in control zebrafish (151 ± 67 vs. 84 ± 37 μl/min, P = 0.004), whereas ejection fraction (EF) was lower (36.3 ± 10.9 vs. 50.9 ± 8.7%, P 0.001), indicating typical high output heart failure derived from anaemia. Additionally, ventricular dysfunction in DOX-treated zebrafish was characterised by low CO (57 ± 38 μl/min) and EF (28.8 ± 10.4%), accompanied by an enlarged ventricle in diastole and systole, representing low output heart failure. For ethanol-treated zebrafish, EF was markedly reduced (39.6 ± 7.2%) indicating a dilated heart, while CO remained unchanged (90 ± 40 μl/min).The epicardial outline method is an effective way of using echocardiography to assess cardiac dysfunction in pathological adult zebrafish, unlocking a major bottleneck in this research field with limited cardiac functional assays.

Patients with severe thiamine deficiency leading to wet beriberi typically present with high output heart failure and predominately right sided symptoms, but a rare and acute form of beriberi known as Shoshin Beriberi can lead to acute cardiovascular collapse. A 52-year-old woman with a history of

High output heart failure is a less frequent cause of heart failure and numerous etiologies should be considered in order to evaluate and treat these patients. A 32-year-old female presented with dyspnea for 1 week. Physical exam revealed bilateral lung crackles, normal S1, S2, and a faint S3, and

Congestive heart failure (CHF) with high cardiac output is an uncommon, yet potentially hemodynamically significant result of arteriovenous malformations. 64-year-old male presented in acute renal and liver failure, with suspected cardiogenic shock. Cardiac catheterization identified an elevated

High output heart failure is an infrequently encountered entity characterized by normal cardiac function with low systemic vascular resistance. It's defined as cardiac output more that 8L/min of cardiac index more than 4.0/min/m2. It is due to an underlying disease process leading to increased

50-year-female presented with features suggestive of high output cardiac failure. She had lumbar discectomy seven years back. Meticulous diagnostic evaluation revealed a large right iliac to lower inferior vena caval communication with continuous shunt. The fistula was closed successfully using a 12 mm muscular ventricular septal occluder. Patient improved dramatically in 24 hours.

Liver diseases have been known to induce changes in systemic hemodynamics and to modify the liver-heart-lung balance. Severe or chronic liver disease may result in several heart or pulmonary complications independently of any other existing cardiac or lung disease. The main liver diseases causing

Presently described is the case of a 41-year-old male patient with signs of high-output right heart failure (HF) due to a possibly iatrogenic arteriovenous fistula (AVF) between the left common iliac artery and the left common iliac vein. Invasively evaluated hemodynamic measurements were consistent with severe shunting, which resulted in precapillary pulmonary hypertension (PH). The AVF was successfully closed with a non-dedicated, 16-mm Amplatzer patent ductus arteriosus occluder (St. Jude Medical, Inc., St. Paul, MN, USA). Although his signs and symptoms were documented to be dramatically improved after closure, because mild PH persisted, adjuvant pulmonary arterial hypertension-targeted treatment with bosentan was initiated to prevent late pulmonary vascular disease.

Objectives Endoglin is a co-receptor for TGFbeta/BMP9/10 signalling and ENG mutations lead to the vascular disorder hereditary haemorrhagic telangiectasia type I (HHT). Endoglin is also required for normal vascular development and angiogenesis, but little is known about endoglin’s role in quiescent adult vascular endothelium. Methods To investigate this role, tamoxifen was administered to adult Cdh5(PAC)-CreERT2;Engfl/fl mice to generate endothelial-specific depletion of endoglin (Eng-iKOe). Cardiac magnetic resonance imaging, myography, vascular casting, microsphere injection, immunohistology, qPCR and aortic telemetry were used to evaluate cardiovascular changes after endoglin knockdown. Results Endothelial-specific loss of endoglin leads to an enlarged heart and cardiomyocyte hypertrophy within 5 weeks, progressing to high output heart failure (HOHF). In vivo aortic telemetry revealed significant loss of aortic pressure within a few days of endoglin depletion. Increased cardiac size and reduced cardiac afterload were confirmed by ventricular pressure loop analysis. As HOHF could result from arteriovenous malformations (AVMs), and these are found primarily in mucocutaneous and pulmonary tissues in HHT, we systematically screened for AVMs using microspheres and vascular casting. Although AVMs were absent in the majority of tissues, they were observed in the pelvic region and may account for the rapid increase in cardiac output. Having also observed an increase of VEGF-A protein in tissues from Eng-iKOe mice, we found that inhibition of VEGFR2 was protective against enlargement of the heart and dilatation of the ventricles. Conclusion Our results showed the essential role of endoglin in the maintenance of adult cardiovasculature through crosstalk with the VEGF signalling pathway.

High output heart failure (HF) and pulmonary hypertension have been demonstrated in patients with prevalent arteriovenous (AV) fistulas. Fistulas with flow >2000 mL/minutes are more likely to induce changes in cardiac geometry and pulmonary artery pressure. The effects of reducing flow in AV access and its implications on HF decompensation and hospitalizations have not been studied. Retrospective analysis of 12 patients who needed hospitalization for acute Congestive Heart Failure (CHF) decompensation with AV access flow of 2 L/minutes (as defined by Kidney Disease Outcomes Quality Initiative (KDOQI)) or more were included in the study. All the patients underwent banding of their inflow at the anastomosis with perioperative access flow measurement. Follow-up period was 6 months. 2D echo was done at 6 months postbanding in addition to access flow and clinical evaluation. Complete data was available for all the 12 patients. Study data was collected on all the 12 patients. Mean age was 64.7 years. The mean access flow pre and postbanding were 3784 mL/minutes and 1178 mL/minutes, respectively (P < 0.001). Eighty percent of the patients had diabetes and 41% had coronary artery disease. There was a statistically significant decrease in cardiac output (pre = 7.06 L/minutes, post = 6.47 L/minutes P = 0.03), pulmonary systolic pressure (pre = 54 mmHg, post = 44 mmHg P = 0.02), left ventricular mass index (LVMI) (pre = 130 g/m(2) , post = 125 g/m(2) P = 0.006) and need for rehospitalization for CHF decompensation. The New York Heart Association (NYHA) staging improved by 1 stage postbanding (P = 0.002). The hospitalization rate was 3.75 ± 1.2 in the 6 months before banding and was decreased to 1.08 ± 1.2 (P = 0.002) postbanding. The hemoglobin level, predialysis systolic blood pressure, calcium phosphorous product and the use of Renin Angiotensin Aldosterone System (RAAS) blockade agents and calcium channel blockers were comparable before and after inflow banding. Flow reduction in high flow fistulas are associated with decreased LVMI and pulmonary artery pressures. There is also a significant reduction in the risk for hospitalization due to acute HF and an improvement in NYHA heart failure stage.

High-output heart failure is not seen as commonly as low-output heart failure and some of the typical guideline recommendations may not benefit patients with high-output failure. High-output failure is caused by several diseases, including thyrotoxicosis and beriberi, highlighted in this article. Thyrotoxicosis, caused by excessive thyroid hormone production, has profound hemodynamic effects. Wet beriberi, affecting predominately the cardiovascular system, is caused by severe thiamine deficiency, most commonly seen in patients with chronic alcoholism or poor nutrition from other causes. Prompt recognition of these infrequently seen syndromes is essential. This article outlines the medical treatment and nursing care needed to return these patients to a normal state.