MC 5687
Stanford, CA 94305
Fax: (650) 723-8392
Duke University School of Medicine, Durham, NC, 05/13/2007
Brigham and Women's Hospital Internal Medicine Residency, Boston, MA, 06/30/2012
Stanford University Cardiovascular Medicine Fellowship, Stanford, CA, 06/30/2015
Stanford University Cardiovascular Medicine Fellowship, Stanford, CA, 06/30/2016
Adult Congenital Heart Disease, American Board of Internal Medicine
Cardiovascular Disease, American Board of Internal Medicine
Echocardiography, National Board of Echocardiography
Internal Medicine, American Board of Internal Medicine
The use of transcatheter edge-to-edge repair (TEER) in patients with advanced heart failure has been shown to reduce hospitalizations and increase survival. As patients with Fontan circulations grow older, a significant proportion of them will develop severe atrioventricular (AV) valve regurgitation in the systemic ventricle. Conventional surgical repair and transplant carry high mortality risk for the adult Fontan patient with progressive heart failure.A 51-year-old female extracardiac Fontan patient developed severe AV valve regurgitation and progressive functional decline. Based on her operative risk for conventional surgical intervention or transplant, TEER using the Abbott MitraClip device was performed. The degree of mitral regurgitation was decreased from severe to moderate regurgitation.This is the first known case describing the use of a successful TEER in an adult patient with an extracardiac Fontan. Given the increasing numbers of patients surviving into adulthood with a Fontan circulation, transcatheter interventions may provide an alternative treatment option to conventional surgeries and medical therapies.
View details for DOI 10.1093/ehjcr/ytac479
View details for PubMedID 36733686
View details for PubMedCentralID PMC9887705
Arrhythmia and sudden cardiac death remain common in repaired tetralogy of Fallot and affect even those with excellent anatomic repairs. Atrial arrhythmia often has mechanisms different from those in acquired heart disease. Ventricular arrhythmia remains a major source of mortality in repaired tetralogy of Fallot. Noninvasive risk stratification is important to identify patients who may benefit from ablation or primary prevention implantable cardioverter defibrillators. Multiple noninvasive risk factors are associated with ventricular arrhythmia, but no universally accepted risk stratification algorithm exists. The mechanism of ventricular arrhythmia is usually attributable to a consistent and discrete set of slowly conducting anatomic isthmuses related to both the native anatomy and the consequences of the surgical repair, which interact with ventricular remodeling to provide arrhythmic substrate. This substrate can be identified during electroanatomic mapping and prophylactically ablated in appropriate patients. This scientific statement discusses the mechanisms and treatment of arrhythmia in repaired tetralogy of Fallot.
View details for DOI 10.1161/HAE.0000000000000084
View details for PubMedID 36263773
View details for DOI 10.1016/j.xjtc.2022.01.018
View details for PubMedID 35403048
We report a case of COVID-19 in an adult single-ventricle patient post-Fontan-to our knowledge, the first report in this population documenting the use of the latest management recommendations for this novel disease. Additionally, this patient had significant pre-existing ventricular dysfunction, valvular disease, and comorbidities including HIV. (Level of Difficulty: Advanced.).
View details for DOI 10.1016/j.jaccas.2020.10.032
View details for PubMedID 33558861
Rheumatic Heart Disease (RHD) affects 41 million people worldwide, mostly in low- and middle-income countries, where it is co-endemic with HIV. HIV is also a chronic inflammatory disorder associated with cardiovascular complications, yet the epidemiology of patients affected by both diseases is poorly understood.Utilizing the Uganda National RHD Registry, we described the echocardiographic findings, clinical characteristics, medication prescription rates, and outcomes of all 73 people carrying concurrent diagnoses of HIV and RHD between 2009 and 2018. These individuals were compared to an age- and sex-matched cohort of 365 subjects with RHD only.The median age of the HIV-RHD group was 36 years (IQR 15) and 86% were women. The HIV-RHD cohort had higher rates of prior stroke/transient ischemic attack (12% vs 5%, p=0.02) than the RHD-only group, with this association persisting following multivariable adjustment (OR 3.08, p=0.03). Prevalence of other comorbidities, echocardiographic findings, prophylactic penicillin prescription rates, retention in clinical care, and mortality were similar between the two groups.Patients living with RHD and HIV in Uganda are a relatively young, predominantly female group. Although RHD-HIV comorbid individuals have higher rates of stroke, their similar all-cause mortality and RHD care quality metrics (such as retention in care) compared to those with RHD alone suggest rheumatic heart disease defines their clinical outcome more than HIV does. We believe this study to be one of the first reports of the epidemiologic profile and longitudinal outcomes of patients who carry diagnoses of both conditions.
View details for DOI 10.1093/cid/ciab681
View details for PubMedID 34382644
View details for DOI 10.1136/heartjnl-2019-316364
View details for PubMedID 34815332
View details for DOI 10.1016/j.ijcchd.2021.100153
BACKGROUND: Indications for a heartliver transplantation (HLT) for Fontan recipients are not well defined. We compared listing characteristics, post-operative complications, and post-transplant outcomes of Fontan recipients who underwent HLT with those of patients who underwent heart-only transplantation (HT). We hypothesized that patients who underwent HLT have increased post-operative complications but superior survival outcomes compared with patients who underwent HT.METHODS: We performed a retrospective review of Fontan recipients who underwent HLT or HT at a single institution. Characteristics at the time of listing, including the extent of liver disease determined by laboratory, imaging, and biopsy data, were compared. Post-operative complications were assessed, and the KaplanMeier survival method was used to compare post-transplant survival. Univariate regression analyses were performed to identify the risk factors for increased mortality and morbidity among patients who underwent HT.RESULTS: A total of 47 patients (9 for HLT, 38 for HT) were included. Patients who underwent HLT were older, were more likely to be on dual inotrope therapy, and had evidence of worse liver disease. Whereas ischemic time was longer for the group who underwent HLT, post-operative complications were similar. Over a median post-transplant follow-up of 17 (interquartile range: 5-52) months, overall mortality for the cohort was 17%; only 1 patient who underwent HLT died (11%) vs 7 patients who underwent HT (18%) (p=0.64). Among patients who underwent HT, cirrhosis on pre-transplant imaging was associated with worse outcomes.CONCLUSIONS: Despite greater inotrope need and more severe liver disease at the time of listing, Fontan recipients undergoing HLT have post-transplant outcomes comparable with those of patients undergoing HT. HLT may offer a survival benefit for Fontan recipients with liver disease.
View details for DOI 10.1016/j.healun.2020.12.008
View details for PubMedID 33485775
The accuracy of liver biopsy to stage fibrosis due to Fontan associated liver disease (FALD) remains unclear. We compared results of biopsy pre-combined heart and liver transplantation (CHLT) to results of whole liver explant. Liver biopsy and explants from 15 Fontan patients (ages 16 - 49, median 28 years) were retrospectively reviewed. Staging was as follows: stage 0: no fibrosis, stage 1: pericellular fibrosis, stage 2: bridging fibrosis, stage 3: regenerative nodules. There is no stage 4. Clinical characteristics including Model of End-stage Liver Disease eXcluding INR and Varices, Ascites, Splenomegaly, and Thrombocytopenia (VAST) scores were collected, and descriptive statistics and Mann-Whitney U tests used to analyze data. All patients had biopsies with at least bridging fibrosis, and all had nodularity on explant; transjugular biopsy never overestimated fibrosis. Explant showed higher grade fibrosis (Stage 3) than pre-CHLT biopsy (Stage 2) in 6 of 15 patients and equal grade of fibrosis (Stage 3) in 9 of 15 patients. Though clinical characteristics varied significantly, VAST score was 2 in all but two patients. Transjugular liver biopsy does not overestimate and can underestimate fibrosis in Fontan patients undergoing CHLT, likely due to the patchy nature of fibrosis in FALD.
View details for DOI 10.1111/ctr.14120
View details for PubMedID 33053213
View details for Web of Science ID 000522637203137
View details for Web of Science ID 000522979100534
View details for Web of Science ID 000522979100541
View details for Web of Science ID 000522979100641
View details for DOI 10.1016/j.jaccas.2020.05.081
View details for PubMedID 32835286
View details for PubMedCentralID PMC7294284
View details for DOI 10.1016/j.ijcchd.2020.100057
View details for DOI 10.1016/j.jaccas.2019.05.031
A 36-year-old female underwent left lower lobectomy with left atrial and left upper pulmonary vein (LUPV) reconstruction with a bovine pericardial patch for an intrathoracic pheochromocytoma. Postoperatively, she developed shortness of breath and transesophageal echocardiography demonstrated LUPV stenosis with increased velocities. Computed tomography angiogram of the chest revealed LUPV stenosis at the left atrium ostium with an area of 39 mm2. Under angiographic and echocardiographic guidance, a 10 19 mm Omnilink Elite uncovered stent was deployed in the LUPV ostia. While reported following left atrial ablation, pulmonary vein stenting can be successful in a pulmonary vein surgically reconstructed with bovine pericardium.
View details for DOI 10.1177/1556984520933962
View details for PubMedID 32639846
Ebstein anomaly comprises approximately 1% of all congenital heart diseases. It occurs when the tricuspid valve fails to properly delaminate from the right ventricle, resulting in a clinical spectrum of abnormal tricuspid valve morphology and right ventricular dysfunction. Due to the anatomy of the tricuspid valve and right ventricle, as well as associated right- and left-sided pathology, patients are at risk for both right and left ventricular failure and the associated symptoms of each. Ebstein patients are also at risk for atrial arrhythmias, due to the atrial enlargement intrinsic to the anatomy, as well as the presence of potential accessory pathways. Arrhythmias are generally poorly tolerated, particularly in the setting of ventricular dysfunction. Cyanosis may also be present in Ebstein patients, due to the common occurrence of atrial communications, which can exacerbate other symptoms of heart failure. Treatment of heart failure can be through pharmacologic and procedural interventions, depending on the underlying cause of heart failure. While early heart failure symptoms may be treated with medical management, most Ebstein patients will require surgery. Various surgical and catheter-based interventions targeting the tricuspid valve and the atrialized right ventricular tissue have been developed to help treat the underlying cause of the heart failure. The optimal timing of transcatheter and surgical intervention in the Ebstein patient to prevent or treat heart failure needs further study.
View details for DOI 10.1007/s10741-020-09930-2
View details for PubMedID 32472521
A 24-year-old Fontan procedure patient underwent surveillance liver cardiac magnetic resonance imaging. Findings were suggestive of hepatocellular carcinoma (HCC). Currently, HCC is diagnosed based on imaging alone. Given her otherwise reassuring clinical profile, she underwent liver biopsy. Pathology demonstrated focal nodular hyperplasia. This raises concern for overdiagnosis of HCC in Fontan patients without tissue confirmation. (Level of Difficulty: Advanced.).
View details for DOI 10.1016/j.jaccas.2019.05.031
View details for PubMedID 34316779
View details for PubMedCentralID PMC8301494
The adult with congenital heart disease (CHD) is at risk of developing atherosclerotic cardiovascular disease (ASCVD). We performed a cross-sectional study to describe established ASCVD risk factors and estimate 10-year and lifetime risk of ASCVD in adults over age 18 with CHD of moderate or great complexity using 3 validated risk assessment tools-the Framingham Study Cardiovascular Disease Risk Assessment, the Reynolds Risk Score, and the ASCVD Risk Estimator. We obtained extensive clinical and survey data on 178 enrolled patients, with average age 37.1 12.6years, 51% men. At least 1 modifiable ASCVD risk factor was present in 70%; the 2 most common were overweight/obesity (53%) and systemic hypertension (24%). Laboratory data were available in 103 of the 178 patients. Abnormal levels of glycated hemoglobin, high-sensitivity C-reactive protein, and high-density lipoprotein were each found in around 30% of patients. The 10-year ASCVD predicted risk using all 3 tools was relatively low (i.e., at least 90% of patients <10% risk), yet the median estimated lifetime risk was 36%. In conclusion, ASCVD risk factors are prevalent in adults with CHD. The risk estimation tools suggest that this population is particularly vulnerable to ASCVD with aging and should undergo guideline-based screening and management of modifiable risk factors.
View details for DOI 10.1016/j.amjcard.2016.09.023
View details for PubMedID 28247847
View details for DOI 10.1016/S0735-1097(16)30951-2
View details for Web of Science ID 000375188701794
Over the last 50 years, improved surgical techniques and progressive medical management have allowed patients with complete or dextro-transposition of the great arteries (D-TGA) to survive into adulthood. Older adult patients underwent an atrial switch procedure (Mustard or Senning operation), whereas the younger cohort of patients with TGA has undergone the arterial switch operation (ASO). The Mustard/Senning maintains the right ventricle as the systemic ventricle, whereas the more recently adopted ASO attempts to restore normal physiologic and anatomic relationships. Neither operation is without consequence. Neither is without consequence and require long term follow up.
View details for DOI 10.1016/j.ccl.2015.07.012
View details for Web of Science ID 000364729200006
View details for PubMedID 26471819
In the absence of specific high-affinity agonists and antagonists, it has been difficult to define the target genes and biological responses attributable to many of the orphan nuclear receptors (ONRs). Indeed, it appears that many members of this receptor superfamily are not regulated by classical small molecules but rather their activity is controlled by interacting cofactors. Motivated by this finding, we have developed an approach to genetically isolate specific receptor-cofactor pairs in cells, allowing us to define the biological responses attributable to each complex. This is accomplished by using combinatorial peptide phage display to engineer the receptor interacting domain of each cofactor such that it interacts selectively with one nuclear receptor. In this study, we describe the customization of PGC-1alpha and its use to study the biology of the estrogen-related receptor alpha (ERRalpha) in cultured liver cells.
View details for DOI 10.1016/j.molcel.2006.10.012
View details for Web of Science ID 000242812000015
View details for PubMedID 17157261