Systemic vascular resistance predicts high-output cardiac failure in patients with high-flow arteriovenous fistula.

AIMS: Patients with high-flow arteriovenous (AV) access are at risk of developing high-output cardiac failure (HOCF) and subsequent hospitalization. However, diagnosing HOCF is challenging and often requires invasive procedures. The role of systemic vascular resistance (SVR) in diagnosing HOCF is underestimated, and its predictive value is limited. Our study aims to identify non-invasive risk factors for HOCF to facilitate early diagnosis and timely surgical interventions. METHODS AND RESULTS: We included 109 patients with high-flow AV access who underwent serial echocardiography. The retrospective cohort was divided into two groups based on their hospitalization due to HOCF. The two groups were matched for age and gender. After a mean follow-up of 25.1 months, 19 patients (17.4%) were hospitalized due to HOCF. The two groups had similar baseline characteristics. However, the HOCF group had a higher value of vascular access blood flow (Qa) (2168 ± 856 vs. 1828 ± 617 mL/min; P = 0.045). Echocardiographic analysis revealed that the HOCF group had more pronounced left ventricular diastolic dysfunction (E/e': 21.1 ± 7.3 vs. 16.2 ± 5.9; P = 0.002), more severe pulmonary hypertension (right ventricular systolic pressure: 41.4 ± 16.7 vs. 32.2 ± 12.8; P = 0.009), a higher Doppler-derived cardiac index (CI) (4.3 ± 0.8 vs. 3.7 ± 1.1; P = 0.031), and a lower Doppler-derived estimated SVR (eSVR) value (5.5 ± 0.3 vs. 6.9 ± 0.2; P = 0.002) than the non-HOCF group. Using multivariable Cox regression analysis, a low eSVR value (<6) emerged as an independent predictor of HOCF hospitalization with a hazard ratio of 9.084 (95% confidence interval, 2.33-35.39; P = 0.001). Receiver operating characteristic curve analysis indicated that CI/eSVR values more accurately predicted HOCF hospitalization [sensitivity: 94.7%, specificity: 51.0%, area under the curve (AUC): 0.75, P < 0.001] than the Qa/cardiac output ratio (AUC: 0.50, P = 0.955), Qa values ≥ 2000 mL/min (AUC: 0.60, P = 0.181), and Qa values indexed for height in metres (AUC: 0.65, P = 0.040). CONCLUSIONS: In patients with high-flow AV access, low eSVR values obtained through non-invasive Doppler echocardiography were associated with a high rate of HOCF hospitalizations. Therefore, routine eSVR screening in these patients might expedite the diagnosis of HOCF.

High-flow arteriovenous fistula in X-linked Alport syndrome: a case report.

Most male X-linked Alport syndrome patients with COL4A5 nonsense mutations experience end-stage kidney failure by 30 years old. Although there is no definition of high-flow arteriovenous fistula, access blood flows greater than 2000 mL/min might predict the occurrence of high-output heart failure. A 50-year-old Japanese man had suffered from proteinuria at 4 years old and sensorineural hearing loss and a lenticular lens at 20 years old. He had started to receive hemodialysis treatment due to end-stage kidney disease at 22 years old. A genetic test confirmed a novel hemizygous nonsense variant COL4A5 c.2980G > T (p.Gly994Ter), and he was diagnosed with X-linked Alport syndrome. COL4A5 c.2980G > T was considered "pathogenic" according to the American College of Medical Genetics and Genomics guidelines and in vitro experiments. Shortness of breath on exertion was exaggerated, his brachial artery blood flow was over 4,236-4,353 mL/min, his cardiac output was 5,874 mL/min, and he needed radial artery banding at 51 years old. After radial artery banding surgery, the brachial artery blood flow decreased to 987-1,236 mL/min, and echocardiography showed a cardiac output at 5100 mL/min with improved E' and E/E'. His shortness of breath on exertion improved gradually. Although rare, high-output heart failure due to high-flow arteriovenous fistula should be kept in mind as a complication in X-linked Alport syndrome patients, and our patient was successfully treated with radial artery banding surgery.

Cure of Refractory Hypotension in a Hemodialysis Patient.

We present a case of a 67-year-old male with end-stage renal disease (ESRD) on hemodialysis who was admitted to the hospital after recurrent falls secondary to postural hypotension. He was not able to tolerate fluid removal on dialysis due to persistent hypotension despite maximal doses of midodrine and developed severe edema. A right heart catheterization revealed raised biventricular filling pressure consistent with right heart failure with low systemic vascular resistance and pulmonary hypertension. Duplex ultrasound of the left arm cephalic arteriovenous fistula (AVF) revealed a blood flow of 5.6 L/min. We hypothesized the cause of his high output heart failure from an AV fistula despite the lack of an increase in blood pressure after compression of the AVF. The AVF was ligated and a tunneled hemodialysis catheter was placed. Immediately after ligation, the patient was able to tolerate fluid removal with dialysis without hypotension, leading to a significant improvement in his edema and shortness of breath. This case highlights the potential adverse cardiovascular effects of AVF and the salutary effects on ligation in appropriate clinical settings.

Management of high-output cardiac failure caused by head and neck AVMs: Percutaneous suture-assisted ethanol and coil embolotherapy.

Purpose: The aim of this study was to describe the treatment technique, outcomes, and complications of Schobinger stage IV head and neck arteriovenous malformations (HNAVMs) with associated high-output cardiac failure (HOCF) using ethanol and coils with the percutaneous suture technique. Methods: From January 2015 to December 2019, 19 patients who had HNAVMs with associated HOCF were treated first with a percutaneous suture of the remarkably dilated dominant drainage vein (RDDOV) and subsequent embolization with coils and ethanol. The percutaneous suture of RDDOV was preferred to be performed, followed by the deployment of coils and the injection of absolute ethanol via transarterial approach, direct puncture approach, or both of them. Treatment outcomes and complication rates were evaluated at follow-up. Results: A total of 19 patients who experienced HNAVMs with HOCF received 19 percutaneous suture procedures and 84 embolization procedures with ethanol and coils. Complete or >90% shunt reduction of the AVM was achieved in 16 patients. Notably, 19 patients with New York Heart Association (NYHA) stage II improved to stage I, and the symptom of dyspnea disappeared after embolization. The symptoms of five patients with bleeding disappeared. All patients presented with cosmetic concerns; Four were cured, and eight had a clearly recognizable improvement. Of note, 19 (100%) patients presented with impairment of daily life, which was resolved. The minor complications were encountered and recovered by the self. No major complications occurred. Conclusion: This study provides evidence that ethanol and coil embolotherapy is effective and safe in treating HOCF caused by HNAVMs with acceptable complications in these cases. The percutaneous suture technique for RDDOV management can act as an adjunct for embolotherapy.

Cardiac and Hemodynamic Manifestations of Hereditary Hemorrhagic Telangiectasia.

The autosomal dominant trait hereditary hemorrhagic telangiectasia (HHT) causes multiorgan dysplastic lesions of the vasculature that can activate multiple physiological cascades leading to a broad array of cardiovascular diseases. Up to 78% of patients with HHT develop hepatic arteriovenous malformations (AVMs), which cause a hyperdynamic circulatory state secondary to hepatic/portal shunting. This condition can eventually progress to high-output cardiac failure (HOCF) with continued peripheral tissue hypoxemia. Treatment for HOCF is often limited to supportive measures (diuretics and treatment of anemia); however, recent studies using systemic bevacizumab have shown promise by substantially reducing the cardiac index. In the context of liver AVMs and high cardiac output, the pulmonary vasculature can also experience high flow. Without adequate dilation of pulmonary vessels, post-capillary pulmonary hypertension can develop. Another form of pulmonary hypertension observed in HHT, pulmonary arterial hypertension, is caused by HHT-related mutations in ENG and ACVRL1 causing congestive arteriopathy. Post-capillary pathogenesis is addressed by reducing the high-output state, whereas the pre-capillary state is treated with supportive mechanisms (diuretics, oxygen) and agents targeting pulmonary vasoreactivity: endothelin-1 receptor antagonists and phosphodiesterase-5 inhibitors. If either form of pulmonary hypertension is left untreated or proves refractory and progresses, the common hemodynamic complication is right heart failure. Targeted right heart therapies involve similar strategies to those of pulmonary arterial hypertension, with several experimental approaches under study. In this review, we describe in detail the mechanisms of pathogenesis, diagnosis, and treatment of the hemodynamic complications and associated cardiovascular diseases that may arise in patients with HHT.

Novel external stenting for reconstruction of high flow arteriovenous fistula.

BACKGROUND: High-flow arteriovenous fistulae (HF-AVF) may lead to adverse cardiac remodeling in hemodialysis patients. We have investigated whether a novel external stent is safe and effective in reducing and stabilizing flow rates during a 1-year follow-up after HF-AVF reconstruction. METHODS: All patients with HF-AVF (access flow rate ⩾ 1500 ml/min), who underwent HF-AVF reconstruction with external stenting in two centers between June 2018 and May 2020, were included in this retrospective analysis. During HF-AVF reconstruction, the dilated vein segment was resected, underwent volume reduction, and was externally stabilized using a braided cobalt-chromium external stent. AVF flow rates were assessed preoperatively, intraoperatively, and at follow up visits using duplex ultrasound. RESULTS: Forty-three HF-AVFs in 42 patients were reconstructed and supported with an external stent (mean age 49 years, range 20-86 years; 74% men). Fifty-one percent were forearm AVFs, 49% were upper arm. The mean preoperative flow rate was 2622 ± 893 ml/min (range: 1500-6000 ml/min) and was decreased to 710 ± 221 ml/min (range: 300-1300 ml/min) intra-operatively after HF-AVF reconstruction. At 6 and 12-months follow-up, the mean flow rates were 1132 ± 320 ml/min (range: 470-1700 ml/min) and 1453 ± 888 ml/min (range: 300-3800 ml/min), respectively. Recurrence of high flow (>1500 ml/min) occurred in 16% and 25% of the patients at 6 and 12 months and primary patency rates were 86% and 70%, respectively. CONCLUSIONS: This early experience with novel external stenting for HF-AVF reconstruction demonstrates that it is a safe and effective method for reducing and stabilizing flow rates up to 1-year post procedure. Additional studies are required to evaluate the durability of this procedure over the longer term and assess its effect on cardiac remodeling.

High-output Cardiac Failure: A Forgotten Phenotype in Clinical Practice.

INTRODUCTION: The knowledge on High-Output Cardiac Failure (HOCF) has greatly improved in the last two decades. One of the advances was the identification of a new phenotype of HOCF, characterized by the absence of ventricular dilation, already associated with liver disease, Arteriovenous Fistulas (AVF), lung disease, myelodysplastic syndromes, and obesity. However, it has been noted that any aetiology can present with one of the two phenotypes, depending on the evolution. OBJECTIVE: The study aims to describe, through an integrative review, the physiopathology and aetiologies of HOCF and to discuss phenotypes associated with this condition. METHODS: Revisions, guidelines, case-controls, cohort studies and clinical studies were searched in MEDLINE and LILACS, using the connectives in the "cardiac output, high" database (MeSH Terms) OR "high cardiac output" (All Fields). DISCUSSION: Two distinct phenotypes are currently described in the HOCF, regardless of the aetiology: 1) one with enlarged cardiac chambers; and 2) with normal heart chambers. The mechanisms related to HOCF are vasodilation, arteriovenous shunts that cause increased microvascular density, Reduced Systemic Vascular Resistance (RSVR), and high metabolism. These mechanisms lead to activation of the renin-angiotensin-aldosterone system, sodium and water retention, activation of neprilysin, of the sodium-glucose-2 transporter, which promote interstitial fibrosis, ventricular remodeling and a consequent increase in cardiac output >8L/min. CONCLUSION: Many aetiologies of HOCF have been described, and some of them are potentially curable. Prompt recognition of this condition and proper treatment may lead to better outcomes.

Successful Treatment of Placental Chorangiomas by Ultrasound-Guided Percutaneous in utero Microcoil Embolization.

Placental chorangiomas can cause a high-output fetal state and increase neonatal morbidity and mortality. There is a paucity of data published describing the optimal treatment of these cases, and methods for occlusion to date include placement of vascular clips, bipolar cautery, injection of alcohol or surgical glue, interstitial laser, and microcoil embolization. We report 2 cases of prenatally diagnosed chorangiomas that caused a high-output fetal state and were successfully treated with microcoil embolization. This case series describes our technique and supports microcoil embolization as a potentially safe and effective antenatal treatment option in symptomatic chorangiomas.

High-output cardiac failure secondary to a post-traumatic iliocaval fistula.

We report a case of a 24-year-old man who had an exploratory laparotomy 3 years earlier for a penetrating hypogastric wound. He presented with congestive heart failure that had progressed over the past 4 months. Transthoracic echocardiography and computed tomography (CT) angiography of the aorta demonstrated a wide arteriovenous fistula between the right common iliac artery and the iliocaval confluence, resulting in the dilatation of the inferior vena cava and of the right heart chambers. The patient was treated by surgical ligation of the right common iliac artery above and below the fistula in conjunction with aortoiliac bypass, thus excluding the shunt.

Subaortic Membranes in Patients With Hereditary Hemorrhagic Telangiectasia and Liver Vascular Malformations.

Background Patients with hereditary hemorrhagic telangiectasia have liver vascular malformations that can cause high-output cardiac failure (HOCF). Known sequelae include pulmonary hypertension, tricuspid regurgitation, and atrial fibrillation. Methods and Results The objectives of this study were to describe the clinical, echocardiographic, and hemodynamic characteristics and prognosis of hereditary hemorrhagic telangiectasia patients with HOCF who were found to have a subaortic membrane (SAoM). A retrospective observational analysis comparing patients with and without SAoM was performed. Among a cohort of patients with HOCF, 9 were found to have a SAoM in the left ventricular outflow tract by echocardiography (all female, mean age 64.8±4.0 years). The SAoM was discrete and located in the left ventricular outflow tract 1.1±0.1 cm below the aortic annular plane. It caused turbulent flow, mild obstruction (peak velocity 2.8±0.2 m/s, peak gradient 32±4 mm Hg), and no more than mild aortic insufficiency. Patients with SAoM (n=9) had higher cardiac output (12.1±1.3 versus 9.3±0.7 L/min, P=0.04) and mean pulmonary artery pressures (36±3 versus 28±2 mm Hg, P=0.03) compared with those without SAoM (n=19) during right heart catheterization. Genetic analysis revealed activin receptor-like kinase 1 mutations in each of the 8 patients with SAoM who had available test results. The presence of a SAoM was associated with a trend towards higher 5-year mortality during follow-up. Conclusions SAoM with mild obstruction occurs in patients with hereditary hemorrhagic telangiectasia and HOCF. SAoM was associated with features of more advanced HOCF and poor outcomes.

The Clinical Relevance and Management of High-Flow Arteriovenous Access.

Obtaining an arteriovenous (AV) access for initiation of hemodialysis is considered the gold standard as it reduces risks of infections, hospitalizations, and need for interventions. It is well documented that creation of AV access can cause or aggravate heart failure. Once AV access is created, blood volume, cardiac contractility, and left ventricular end-diastolic volume increase in a nonphysiologic fashion resulting in an overall increase in cardiac output. Left ventricular hypertrophy, diastolic dysfunction, pulmonary hypertension, and high-output cardiac failure can occur. AV accesses that have blood flows greater than 1.5 L per minute are of high risk. When access flow exceeds 25% to 30% of cardiac output, the risk of developing high-output heart failure increases. Studies suggest that a blood flow (Qa)/cardiac output (CO) ratio of greater than 0.30 should be used as a screening tool to perform further cardiac testing. Depending on the severity of symptoms, management can range from banding procedure (flow reduction) or need for total abandonment of the AV access. The complications associated with high-flow AV accesses are often overlooked. Nephrologists and vascular access experts should work in tandem to mitigate potential harm to patients on dialysis who are afflicted by this condition.

Mobile Mitral and Aortic Valvular Masses in Patients With Hereditary Hemorrhagic Telangiectasia Receiving Intravenous Bevacizumab.

Bevacizumab is now an emerging treatment option for severe hereditary hemorrhagic telangiectasia-related bleeding including epistaxis and gastrointestinal tract bleeding. The impact of long-term intravenous bevacizumab therapy on cardiac structure and function is unknown. We describe 3 patients receiving intravenous bevacizumab therapy for severe hereditary hemorrhagic telangiectasia-related bleeding who were found to have abnormal mobile masses on the mitral valve (n=2) and aortic valve (n=1). The clinical impact of these findings is unknown and requires further study.

Systemic bevacizumab for high-output cardiac failure in hereditary hemorrhagic telangiectasia: an international survey of HHT centers.

BACKGROUND: Systemic bevacizumab is a novel targeted anti-angiogenic therapy for high-output cardiac failure (HOCF) in hereditary hemorrhagic telangiectasia (HHT) but published data is limited. This survey-based study measured physician-reported safety, effectiveness and current treatment practices for systemic bevacizumab in HHT-HOCF. METHODS: A 27-item survey was sent to center directors of 31 international HHT Centers of Excellence. RESULTS: Response rate was 74% with centers reporting 150 total patients receiving systemic bevacizumab for HHT-HOCF. Approximately two-thirds of centers had treated ≥5 patients. All centers utilize a 5 mg/kg dose for induction treatment and most administer 6 doses (range, 4-6) every 2 weeks, although maintenance regimens varied considerably. Center directors reported bevacizumab to be effective, with 55% reporting significant improvement in cardiac index and HOCF symptoms in most patients treated with bevacizumab, although normalization of cardiac parameters was uncommon. Adverse events were uncommon with three-quarters of centers reporting adverse event rates < 10%. Discontinuation for adverse events or ineffectiveness was rare. Bevacizumab was typically administered by hematologists and pulmonologists (50 and 39% of centers, respectively), with highly variable thresholds for initiation. Although half the centers reported difficulty with the insurance approval process, 70% of centers were ultimately able to obtain coverage for most or all of their patients. CONCLUSIONS: Systemic bevacizumab is a widely-used therapy for HHT-HOCF with reasonable safety and effectiveness. HHT centers appear to vary considerably in maintenance treatment practices and disease severity thresholds for initiation of bevacizumab in HHT-related HOCF.

Acceso venoso para hemodiálisis y repercusión crónica en el sistema cardiovascular / Hemodialysis venous access and chronic impact on cardiovascular system

En el tratamiento de enfermos renales en fase terminal, se realizan accesos vasculares para hemodiálisis. Son hechos habitualmente, en las venas de los miembros superiores, especialmente la técnica de Brecia y Cimino (fístula arteriovenosa latero lateral de la cefálica y la radial en la muñeca). La mayor complicación, directamente relacionada con un flujo excesivo por la fístula arteriovenosa, es la insuficiencia cardíaca congestiva. Se presenta el caso de un paciente con una fístula arteriovenosa (iatrogénica) que causó una insuficiencia cardiaca congestiva. El paciente, hipertenso conocido, tuvo un acceso venoso de más de 10 años de evolución (por un aparente diagnóstico y para una futura hemodiálisis que nunca fue efectuada). Acudió a consulta con disnea y edemas periféricos. Al examen físico se encontró la tensión arterial en 160 y 100 mm Hg, signos clínicos de cardiomegalia, edemas periféricos, ingurgitación yugular y hepatomegalia. Se palpó un thrill sistodiastólico en la muñeca izquierda, donde presentaba una cicatriz. Pudo observarse marcada dilatación y endurecimiento de todas las venas superficiales del plexo braquial de ese lado, (arterialización del árbol venoso del miembro superior izquierdo hasta las venas superficiales del hemitórax). Se diagnosticó una insuficiencia cardiaca de gasto alto, mejoró con el tratamiento habitual, pero continuó con la malformación venosa adquirida. Fue un caso muy llamativo, que muestra una complicación poco frecuente de los accesos venosos para hemodiálisis y también una causa mencionada, pero escasamente vista, de insuficiencia cardiaca de gasto elevado(AU)

In the treatment of renal patients in terminal phase. Vascular accesses are used for hemodialysis. They are usually performed in the veins of the upper limbs, especially using Brecia and Cimino technique (lateral arteriovenous fistula of the cephalic and radial at the wrist). The major complication, directly related to an excessive flow of arteriovenous fistula, is congestive heart failure. We present the case of a patient with an arteriovenous (iatrogenic) fistula that caused a congestive heart failure. He is hypertensive and had venous access for over 10 years of evolution (for an apparent diagnosis and for future hemodialysis, which was never performed). He went to the clinic with dyspnea and peripheral edema. Physical examination revealed blood pressure of 160 and 100 mm Hg, clinical signs of cardiomegaly, peripheral edema, jugular engorgement and hepatomegaly. We found a systodiastolic thrill on his left wrist, where there is a scar. A marked dilation and hardening of all the superficial veins of the brachial plexus on that side was observed, that is arterialization of the venous tree of the left upper limb to the superficial veins of hemitorax. The diagnosis was high output heart failure. He improved with the usual treatment, but the acquired venous malformation continued in an iatrogenic manner. It was a very striking case because of the infrequent complication of venous accesses for hemodialysis and because for rarely seen elevated heart failure(AU)

Dysplastic megalencephaly phenotype presenting with prenatal high-output cardiac failure.

Dysplastic megalencephaly, also known as bilateral hemimegalencephaly, is a rare cerebral malformation characterized by bilateral cerebral hemisphere overgrowth and extensive malformation of cortical development. Affected patients present clinically with intractable seizures, severe neurological impairment and global developmental delay. There is a small body of literature reporting megalencephaly's association with neonatal high-output cardiac failure and a lack of literature describing prenatal findings. We report a case of dysplastic megalencephaly presenting with progressive high-output cardiac failure during fetal life. Prenatal and postnatal imaging findings as well as neonatal course are described. A companion case with similar imaging findings will help illustrate the prenatal imaging characteristics of this association. Knowledge of this potential complication related to dysplastic megalencephaly may help guide parental counseling and obstetric management.

High-flow arteriovenous fistula and heart failure: could the indexation of blood flow rate and echocardiography have a role in the identification of patients at higher risk?

BACKGROUND: Although only high-flow arteriovenous fistulas (AVFs) are postulated to cause high-output cardiac failure (HOCF), there are currently no universally accepted criteria defining a high-flow fistula. METHODS: To verify if vascular access blood flow (Qa) ≥ 2000 ml/min provides an accurate definition of high-flow fistula, we selected 29 consecutive patients with Qa ≥ 2000 ml/min at color-duplex ultrasound examination and assessed them for the presence of cardiac failure symptoms; transthoracic echocardiography was also performed. RESULTS: Nineteen patients (65%) had heart failure symptoms and were classified with HOCF. At receiver operating characteristic (ROC) curve analysis, Qa ml/min values did not identify patients with heart failure symptoms but when AVF blood flow was indexed for height2.7, Qa ≥ 603 ml/min/m2.7 detected the occurrence of HOCF with good accuracy (sensitivity 100%, specificity 60%, efficiency 86%, positive predictive value 83%, negative predictive value 100%, area under curve 0.75). At echocardiographic evaluation, patients with Qa ≥ 603 ml/min/m2.7 had a more severe increase of left ventricular mass (63 ± 18 vs. 47 ± 7 g/m2.7, p < 0.003), left ventricular diastolic volume (140 ± 42 vs. 109 ± 14 ml, p < 0.007), left atrial volume (53 ± 23 vs. 39 ± 5 ml/m2, p < 0.015), a higher incidence of diastolic dysfunction (70 vs. 17%, p < 0.019) and higher CO reduction after AVF manual compression (2151 ± 875 vs. 1292 ± 527 ml/min, p < 0.009) than patients with Qa < 603 ml/min/m2.7. CONCLUSIONS: Indexation of AVF blood flow should be considered in defining high-flow fistula because the effect of Qa may differ in individuals of different sizes. A Qa value ≥ 603 ml/min/m2.7 and its association with some echocardiographic alterations could identify patients at higher risk for HOCF.

High-Output Cardiac Failure and Coronary Steal With an Arteriovenous Fistula.

Creation of an arteriovenous access for hemodialysis can provoke a sequence of events that significantly affects cardiovascular hemodynamics. We present a 78-year-old man with end-stage renal disease and concomitant coronary artery disease previously requiring coronary artery bypass grafting including a left internal mammary graft to the left anterior descending artery, ischemic cardiomyopathy with left ventricular systolic dysfunction, and severe aortic stenosis who developed hypotension unresponsive to medical therapy after recent angioplasty of his ipsilateral arteriovenous fistula for high-grade outflow stenosis. This case highlights the long-term effects of dialysis access on the cardiovascular system, with special emphasis on complications such as high-output cardiac failure and coronary artery steal syndrome. Banding of the arteriovenous fistula provided symptomatic relief with a decrease in cardiac output. Avoidance of arteriovenous access creation on the ipsilateral upper extremity in patients with a left internal mammary artery bypass graft may prevent coronary artery steal syndrome.

High-Output Cardiac Failure Due to Hereditary Hemorrhagic Telangiectasia: A Case of an Extra-Cardiac Left to Right Shunt.

High-output cardiac failure is a rare complication of hereditary hemorrhagic telangiectasia and can potentially be mistaken for other entities. We present a case of high-output cardiac failure because of large hepatic arteriovenous malformations, review the literature regarding the cardiac manifestations of the disease, and discuss the possible differential diagnoses.

Serial Measurement of Superior Vena Cava Flow in Evaluation of the Clinical Severity of Pial Arteriovenous Fistula in an Infant.

Background Pial arteriovenous fistula (AVF) is composed of one or more direct arterial feeding vessels with a single draining vein without nidus. A patient with the disease with high-flow AV shunting in the neonatal period not only suffers from high-output cardiac failure but also shows secondary neurological sequelae. In vein of Galen aneurysmal malformation, superior vena cava (SVC) flow measurements provide useful prognostic information. Case Presentation We measured serial SVC flow in a male infant with pial AVF. The term infant presented with tachypnea, a heart murmur, and a cranial bruit after birth, and cranial magnetic resonance imaging and computed tomographic angiography revealed a pial AVF on the left sylvian fissure. SVC flow was at the upper normal limit at presentation. After 1 month, SVC flow gradually increased up to fourfold. Surgical resection of the pial AVF was performed and diagnosed as pial AVF on day 62. The SVC flow immediately decreased thereafter. Conclusion SVC flow reflects the shunt volume and may be a useful parameter for evaluating the optimal timing and effectiveness of intervention in pial AVF.