Biomedical subjects

Meryl S Cohen

Publications and source records attributed to Meryl S Cohen.

11 recordsLinked to original sources

PubMed2006

Heterotaxy syndrome with functional single ventricle: does prenatal diagnosis improve survival?

BACKGROUND: Despite improved outcome for many single ventricle lesions, staged reconstruction for heterotaxy syndrome with a functional single ventricle continues to have a high mortality. Prenatal identification of heterotaxy syndrome may improve long-term survival. METHODS: Our database was reviewed from January 1996 to December 2004 for patients with heterotaxy syndrome. Assessment was made for prenatal diagnosis and echocardiographic characteristics of heterotaxy syndrome. We sought to assess the accuracy of fetal echocardiography in the diagnosis of heterotaxy syndrome and determine whether prenatal diagnosis and other risk factors have an impact on survival in patients with heterotaxy syndrome. RESULTS: Of 81 patients that met criteria, 43 (53%) had prenatal diagnosis. Prenatal diagnosis had high specificity and positive predictive value for all findings but had low sensitivity for anomalous pulmonary veins. Among the 70 patients born alive, survival was 60% with median follow-up of 51.4 months (range, 6.5 to 109.7 months). Prenatal diagnosis did not improve survival (p = 0.09). None of the 11 patients with complete heart block (CHB) survived past 3 months of age. Two patients underwent heart transplantation as their first intervention and have survived. CHB and anomalous pulmonary venous connection were associated with shorter duration of survival. CONCLUSIONS: Prenatal diagnosis of heterotaxy syndrome does not improve survival in patients who undergo single ventricle reconstruction. The most potent risk factors for poor outcome (CHB, anomalous pulmonary veins) are likely not impacted by identification in utero. In light of the poor outcome, cardiac transplantation as an initial therapy may be a viable option for some patients.

Echocardiography↗

PubMed2006

Real-time 3-dimensional echocardiographic imaging of congenital heart disease using matrix-array technology: freehand real-time scanning adds instant morphologic details not well delineated by conventional 2-dimensional imaging.

OBJECTIVE: We sought to investigate whether real-time (RT) 3-dimensional echocardiography (RT3D) using matrix-array technology could resolve a specific morphologic detail that could not be well resolved during conventional 2-dimensional (2D)/Doppler echocardiographic imaging of congenital heart disease. BACKGROUND: Although 2D echocardiography is currently the primary imaging modality of congenital heart disease, there are still some anatomic details that cannot be well delineated by that modality. METHODS: In all, 70 patients underwent RT3D examination using matrix-array transducer. Applying the standard sweeping technique as for 2D imaging, freehand RT imaging was used for immediate feedback. The 2D examinations of the last 23 consecutive patients were used to validate the additional value of RT3D by 3 examiners blinded to the findings of RT3D. RESULTS: The adequacy of 2D imaging to resolve the morphologic detail in question ranged from 30% to 70%, whereas RT3D imaging was considered successful in delineating the morphologic detail in 80% to 100% of patients instantly. The image resolution was superior or equivalent to that obtained by 2D imaging. Heart valves, septal defects, and volumetric valvular and vascular color flow morphologies were well delineated by RT3D. CONCLUSION: Matrix-array RT3D is a significant breakthrough technology that allowed instant visualization of cardiac anatomic details that could not be well delineated by 2D imaging. Further improvements of some technical limitations should make RT3D matrix-array cardiac imaging a significant modality in the field of echocardiographic imaging of congenital cardiac anomalies.

Adolescent↗

PubMed2006

Neo-aortic valvar function after the arterial switch.

OBJECTIVES: The purpose of our study was to assess the prevalence and progression, during childhood and adolescence, of dilation of the neo-aortic root, and neo-aortic valvar regurgitation, and to identify risk factors for such dilation and regurgitation, after the arterial switch operation. METHODS: We included all patients who had undergone an arterial switch operation at The Children's Hospital of Philadelphia, and had been followed for a minimum of 4 years, and had at least 2 postoperative echocardiograms. Neo-aortic valvar regurgitation was quantitatively assessed, and measurements were made of the neo-aortic root at the level of the basal attachment of the leaflets, mid-sinusal level, and the sinutubular junction. RESULTS: We found 82 patients who satisfied the criterions for inclusion, of whom 52 patients had transposition with an intact ventricular septum, and 30 had either an associated ventricular septal defect or double outlet right ventricle. The median follow-up time was 8.8 years (4.1 to 16.4 years). The neo-aortic valve had been replaced in 1 patient. Of the patients, 3 had moderate, 66 had trivial to mild, and 12 had no neo-aortic valvar regurgitation at their most recent follow-up. The regurgitation had progressed by at least 1 grade in 38 of the 82 patients (46.4%). Neo-aortic dilation was noted at the basal attachment of the leaflets, and at mid-sinusal level, which was out of proportion to somatic growth. CONCLUSIONS: At mid-term follow-up, significant neo-aortic valve regurgitation is present in 3.7%, and trivial to mild regurgitation in 81.4% of patients. The regurgitation progressed in almost half of the patients over time. We also noted progressive dilation of the neo-aortic root out of proportion to somatic growth.

Aortic Valve Insufficiency↗

PubMed2005

Does fetal diagnosis make a difference?

Fetal echocardiography has clearly made a difference in the world of pediatric cardiology today. It has taught us much about the natural history of fetal cardiac disease, and with ongoing collaborative studies, it should continue to enhance our knowledge base. Fetal echocardiography has enabled us to identify potential candidates for fetal cardiac intervention and has promoted the development of an exciting new discipline within pediatric cardiology. We hope that the recognition of critical congenital heart disease in utero improves the long-term outcome of our patients, including neurodevelopmental outcome and quality of life.

Echocardiography↗

PubMed2005

Chronic hypoxemia increases myocardial cytochrome oxidase.

OBJECTIVE: Cyanotic patients have potentially decreased tissue oxygen tension. Cytochrome oxidase catalyzes the reduction of oxygen and is integral to adenosine triphosphate production. Cytochrome oxidase subunit I, the active site, is encoded by mitochondrial DNA. Using a newborn swine model of chronic hypoxemia, we evaluated ventricular cytochrome oxidase subunit I mRNA and protein expression and assessed cytochrome oxidase activity. METHODS: Thirty-two newborn piglets underwent thoracotomy and placement of a pulmonary artery-to-left atrium shunt or sham operation. Two weeks later, partial pressure of arterial oxygen, hematocrit, and left ventricular shortening fraction values were compared with baseline values. Northern blot hybridization and protein immunoblotting for ventricular cytochrome oxidase subunit I were performed. Cytochrome oxidase kinetic activity was measured. Heme a,a3 content and turnover number were determined. Significance was assessed with a t test. RESULTS: Baseline partial pressure of arterial oxygen and hematocrit values were similar. Hypoxemic piglets had a lower partial pressure of arterial oxygen of 38 +/- 10 mm Hg (P < .001) and higher hematocrit value of 31.4% +/- 2.9% (P < .001) compared with a partial pressure of arterial oxygen of 140 +/- 47 mm Hg and hematocrit value of 24.6% +/- 3.9% after the sham operation. Baseline and postprocedure left ventricular shortening fraction were similar within and between groups. Chronic hypoxemia increased right ventricular and left ventricular cytochrome oxidase I mRNA and protein by more than 1.4-fold. Cytochrome oxidase activity increased significantly in hypoxemia by 2.5-fold compared with that seen after the sham operation. Heme a,a3 content and turnover number increased by 1.5-fold during hypoxemia. CONCLUSIONS: Chronic hypoxemia increases cytochrome oxidase I message, protein expression, and activity. The increase in kinetics was due to increased enzyme content and catalytic activity. This is a possible adaptive mechanism that might preserve organ function during chronic hypoxemia.

Animals↗

PubMed2005

Surgical management of unbalanced atrioventricular canal defect.

Approximately 10% of endocardial cushion defects exhibit unbalance at the atrioventricular inlet. When the atrioventricular valve sits more over one ventricle than the other, the contralateral ventricle is typically hypoplastic. Surgical intervention for unbalanced atrioventricular canal has a much higher morbidity and mortality than for the balanced form of the defect. With unbalanced atrioventricular canal to the right, no universal criteria are in place to choose single versus biventricular repair. In many cases, risk factors have been extrapolated from other lesions with left ventricular hypoplasia. Even if biventricular repair is successful, the reoperation rate is high for this lesion. Little data exist in the literature regarding left unbalanced atrioventricular canal. In general, right ventricular hypoplasia is better tolerated than left ventricular hypoplasia, and biventricular repair is usually possible. If cyanosis or high systemic venous pressure results, the one and one half ventricle repair (biventricular repair with bidirectional Glenn anastomosis) is an option. This article reviews the present understanding of unbalanced atrioventricular canal and discusses diagnostic and surgical strategies for this complex lesion.

Atrioventricular Node↗

PubMed2004

Acute cardiovascular effects of fetal surgery in the human.

BACKGROUND: Prenatal surgery for congenital anomalies can prevent fetal demise or alter the course of organ development, resulting in a more favorable condition at birth. The indications for fetal surgery continue to expand, yet little is known about the acute sequelae of fetal surgery on the human cardiovascular system. METHODS AND RESULTS: Echocardiography was used to evaluate the heart before, during, and early after fetal surgery for congenital anomalies, including repair of myelomeningocele (MMC, n=51), resection of intrathoracic masses (ITM, n=15), tracheal occlusion for congenital diaphragmatic hernia (CDH, n=13), and resection of sacrococcygeal teratoma (SCT, n=4). Fetuses with MMC all had normal cardiovascular systems entering into fetal surgery, whereas those with ITM, CDH, and SCT all exhibited secondary cardiovascular sequelae of the anomaly present. At fetal surgery, heart rate increased acutely, and combined cardiac output diminished at the time of fetal incision for all groups including those with MMC, which suggests diminished stroke volume. Ventricular dysfunction and valvular dysfunction were identified in all groups, as was acute constriction of the ductus arteriosus. Fetuses with ITM and SCT had the most significant changes at surgery. CONCLUSIONS: Acute cardiovascular changes take place during fetal surgery that are likely a consequence of the physiology of the anomaly and the general effects of surgical stress, tocolytic agents, and anesthesia. Echocardiographic monitoring during fetal surgery is an important adjunct in the management of these patients.

Adult↗

PubMed2004

Diagnostic assessment before Fontan operation in patients with bidirectional cavopulmonary anastomosis: are noninvasive methods sufficient?

OBJECTIVES: This study was designed to determine if a subset of patients who have undergone bidirectional cavopulmonary anastomosis could be identified in which catheterization was of little benefit before completion of the Fontan procedure. BACKGROUND: Diagnostic evaluation before Fontan procedure has typically included cardiac catheterization. However, the overall management strategy for patients with functional single ventricle has evolved to include staging bidirectional cavopulmonary anastomosis in most, and it has become uncommon to exclude patients from Fontan based on catheterization data. METHODS: Patients who underwent bidirectional cavopulmonary anastomosis and had complete echocardiograms and catheterizations within three months of each other between January 1992 and October 1997 were evaluated with a series of clinical and echocardiographic characteristics to identify a subset in whom catheterization was predicted to be of little added value ("no-cath" group). The predictive value and sensitivity of these criteria in excluding patients who required additional intervention, were excluded from Fontan, or died within 30 days of Fontan was determined. RESULTS: A total of 99 patients who underwent bidirectional cavopulmonary anastomosis at 6.7 months (range 2.9 months to 14 years) were studied; 46 met criteria for the "no-cath" group. Noninvasive criteria stratified all patients who died (n = 5) or did not proceed to Fontan (n = 1) and 9 of 11 who required additional interventions to the "cath" group. Thus, the negative predictive value of these criteria was 93%. CONCLUSIONS: Our data suggest that catheterization before Fontan could be avoided in a large percentage of patients without adversely affecting outcome; prospective evaluation of this strategy is warranted.

Adolescent↗

PubMed2004

Fetal and childhood onset of adult cardiovascular diseases.

Childhood onset of adult cardiovascular disease has become a significant public health problem. Whether genetic, environmental, or fetal influences are the primary culprits in the epidemic of the cardiovascular disease seen today remains unknown. The benefits of an overall physically active lifestyle that includes weight control, lower blood pressure, avoidance of tobacco use, and consistent exercise are clear and can impact the overall health of children and adolescents. Physicians who care for children and adolescents must begin to incorporate screening of adult cardiovascular disorders into their practice. Better understanding of the etiology of these disease states will bring with it enhanced preventive and targeted therapies.

Adolescent↗

PubMed2003

Neo-aortic root dilation and valve regurgitation up to 21 years after staged reconstruction for hypoplastic left heart syndrome.

OBJECTIVES: We sought to assess the prevalence and progression of neo-aortic root dilation and valvar regurgitation after staged reconstruction for hypoplastic left heart syndrome (HLHS). BACKGROUND: In HLHS, the pulmonary valve functions as the neo-aortic valve. Neo-aortic valve dysfunction has been observed after arterial switch operation and the Ross procedure. METHODS: Patients with HLHS born before January 1995 who had the Fontan operation and had serial echocardiograms were included. Echocardiograms were reviewed preoperatively, after each surgical reconstruction, and at most recent follow-up for neo-aortic root size and severity of neo-aortic regurgitation (AR). Potential risk factors for neo-aortic valve dysfunction were assessed. RESULTS: Fifty-three patients met inclusion criteria. Bidirectional superior cavopulmonary anastomosis as an interim procedure was performed in 39 patients (74%). Median duration of follow-up was 9.2 (range 5.1 to 21) years. During follow-up, the neo-aortic root progressively dilated out of proportion to body size over time, with 52 patients (98%) having a Z-score >2 at most recent follow-up. Neo-AR was present in 61% of patients at most recent follow-up, with progression over time in 26 patients (49%). However, neo-AR was more than mild in only three patients. Significantly larger neo-aortic root Z-scores were observed in patients with any degree of neo-AR at most recent follow-up. No other anatomic or clinical variables correlated with severity of neo-AR or root dilation. CONCLUSIONS: After staged reconstruction for HLHS, neo-aortic root dilation and neo-AR progress over time. Early volume unloading does not have a beneficial impact on dilation of the neo-aortic root. These findings raise concerns about neo-aortic valve function into adulthood.

Aortic Valve Insufficiency↗

PubMed2002

Influence of congenital heart disease on survival in children with congenital diaphragmatic hernia.

OBJECTIVE: We sought to assess outcome in patients with CDH and HD to determine if LHR is also predictive of outcome in this subset of patients. STUDY DESIGN: We carried out a retrospective review (April 1996-October 2000) of patients with isolated CDH (n = 143, 82.2%) and patients with HD (n = 31, 17.8%) to determine the incidence of additional anomalies, survival to term, CDH repair, cardiac repair, and survival to discharge. Survival based on LHR was analyzed in a subset of fetuses. RESULTS: The risk of death from birth to last follow-up was 2.9 times higher for patients with CDH plus HD than for patients with CDH alone (P <.0001). Of 11 patients with CDH plus HD who had CDH repair (5 of whom also had HD repair), 5 survived. All 10 patients with an LHR <1.2 died; 3 of 6 with an LHR >1.2 survived (Fisher exact test, P =.04). CONCLUSION: Heart disease remains a significant risk factor for death in infants with CDH. The LHR helps predict survival in this high-risk group of patients.

Abnormalities, Multiple↗