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Gruschen R Veldtman

Publications and source records attributed to Gruschen R Veldtman.

13 recordsLinked to original sources
PubMed2006

Sildenafil therapy for pulmonary arterial hypertension associated with atrial septal defects.

BACKGROUND: There is increasing evidence for beneficial effects of the type 5 phosphodiesterase inhibitor, sildenafil, in idiopathic pulmonary arterial hypertension (PAH). The effects of sildenafil in severe PAH associated with an atrial septal defect (ASD) have not been clearly delineated. METHODS: This extended case series reviews our experience with sildenafil treatment in three patients with severe PAH and Eisenmenger syndrome associated with an ASD. Case notes were reviewed for baseline and follow-up anatomic, clinical and haemodynamic characteristics. RESULTS: Of three patients identified, median age 44.3 years (range, 28 to 59 years), two had large secundum ASDs and the other a sinus venous defect. All patients had severe PAH and were desaturated at rest and/or during exercise. Sildenafil was started because of progressive and severe effort intolerance. All patients experienced symptomatic improvement, had higher arterial saturations (range 8-19%) and improvement in effort tolerance (88 m and 56 m improvement in 6-min walk test distance (MWTD) in two patients). Right ventricular (RV) function and Doppler derived RV systolic pressure improved in two patients. Pulmonary arterial pressures decreased in two patients who had cardiac catheterization (range 4 to 14 mm Hg). Pulmonary vascular resistance decreased from 7.58 to 3.8 Wood's units in one patient who is now awaiting surgery. Another patient developed significant pulmonary vasoreactivity (8.3 to 6.2 Wood's units with 100% oxygen) after 16 months of sildenafil therapy. CONCLUSIONS: Sildenafil not only relieves symptoms associated with severe PAH in patients with large ASDs, but also improves pulmonary arterial hemodynamics and RV function.

Adult↗
PubMed2006

Hepatic changes in the failing Fontan circulation.

BACKGROUND: The failing Fontan circulation is associated with hepatic impairment. The nature of this liver injury is poorly defined. OBJECTIVE: To establish the gross and histological liver changes of patients with Fontan circulation relative to clinical, biochemical and haemodynamic findings. METHODS: Patients were retrospectively assessed for extracardiac Fontan conversion between September 2003 and June 2005, according to an established clinical protocol. Twelve patients, mean age 24.6 (range 15.8-43.4) years were identified. The mean duration since the initial Fontan procedure was 14.1 (range 6.9-26.4) years. RESULTS: Zonal enhancement of the liver (4/12) on CT was more common in patients with lower hepatic vein pressures (p = 0.007), and in those with absent cardiac cirrhosis on histological examination (p = 0.033). Gastro-oesophageal varices (4/12) were more common in patients with higher hepatic vein pressure (21 (6.3) vs 12.2 (2.2) mm Hg, p = 0.013) and associated with more advanced cirrhosis (p = 0.037). The extent of cirrhosis (7/12) was positively correlated with the hepatic vein pressure (r = 0.83, p = 0.003). A significant positive correlation was found between the Fontan duration and the degree of hepatic fibrosis (r = 0.75, p = 0.013), as well as presence of broad scars (r = 0.71, p = 0.021). Protein-losing enteropathy (5/12) occurred more frequently in patients with longer Fontan duration (11.7 (3.2) vs 17.9 (6.1) years, p = 0.038). CONCLUSIONS: Liver injury, which can be extensive in this patient group, is related to Fontan duration and hepatic vein pressures. CT scan assists non-invasive assessment. Cardiac cirrhosis with the risk of developing gastro-oesophageal varices and regenerative liver nodules, a precursor to hepatocellular carcinoma, is common in this patient group.

Adolescent↗
PubMed2006

Esmolol-assisted balloon and stent angioplasty for aortic coarctation.

The objective of this study was to evaluate the effectiveness and safety of esmolol-induced negative ino- and chronotropism during stent/balloon angioplasty for aortic coarctation. Balloon angioplasty and stent placement have become widely accepted therapies for native and recurrent coarctation of the aorta (CoA). Trauma to the vessel wall and stent migration related to forward displacement of the balloon and/or stent by cardiac output, are the most common complications. Controlling stroke volume and heart rate may assist in balloon stability and accurate deployment of stents. All methods currently used to achieve this have significant limitations. We describe our experience using esmolol to control stroke volume and heart rate during balloon/stent angioplasty of CoA. We performed a retrospective review of all patients who had intravenous esmolol during percutaneous treatment of CoA. Six interventions were performed in six patients: coarctation stent angioplasty in five patients (two native coarctation) and balloon angioplasty alone in one patient. The median systolic blood pressure achieved during the procedure was 65 mmHg (range, 57-75) representing a median reduction of 40 mmHg (range, 20-80; p = 0.008) from baseline. The median heart achieved was 50 beats/min (range, 20-80), representing a median reduction of 20 beats/min (range, 15-90, p = 0.048) from baseline. Optimal stent position was obtained in all patients. Intravenous esmolol controls periprocedural hemodynamics effectively and safely during percutaneous therapy for aortic coarctation, thereby aiding accurate stent placement. Further evaluation of its use during other percutaneous left heart interventions is required.

Adolescent↗
PubMed2006

Correlations with operative anatomy of real time three-dimensional echocardiographic imaging of congenital aortic valvar stenosis.

OBJECTIVE: To define the anatomic characteristics of the congenitally malformed and severely stenotic aortic valve using trans-thoracic real time three-dimensional echocardiography, and to compare and contrast this with the valvar morphology as seen at surgery. DESIGN: Prospective cross-sectional observational study. SETTING: Tertiary centre for paediatric cardiology. METHODS: All patients requiring aortic valvotomy between December 2003 and July 2004 were evaluated prior to surgery with three-dimensional echocardiography. Full volume loop images were acquired using the Phillips Sonos 7500 system. A single observer analysed the images using "Q lab 4.1" software. The details were then compared with operative findings. RESULTS: We identified 8 consecutive patients, with a median age of 16 weeks, ranging from 1 day to 11 years, with median weight of 7.22 kilograms, ranging from 2.78 to 22 kilograms. The measured diameter of the valvar orifice, and the number of leaflets identified, corresponded closely with surgical assessment. The sites of fusion of the leaflets were correctly identified by the echocardiographic imaging in all cases. Fusion between the right and non-coronary leaflets was identified in half the patients. Dysplasia was observed in 3 patients, with 1 patient having nodules and 2 shown to have excrescences. At surgery, nodules were excised, and excrescences were trimmed. The dysplastic changes correlated well with operative findings, though statistically not significant. CONCLUSION: We recommend trans-thoracic real time three-dimensional echocardiography for the assessment of the congenitally malformed aortic valve, particularly to identify sites of fusion between leaflets and to measure the orificial diameter. The definition of nodularity, and the prognosis of nodules based on the mode of intervention, will need a comparative study of patients submitted to balloon dilation as well as those undergoing surgical valvotomy.

Aortic Valve Stenosis↗
PubMed2006

New technique for fenestration of the interatrial septum.

Achieving controlled flow between the systemic and pulmonary venous circulations is desirable in many complex congenital heart diseases. This includes the Fontan circulation, primary pulmonary hypertension, double inlet ventricles, or hypoplastic left heart with obstruction to the atrioventricular valve. As no specific device is available for this purpose, we developed a balloon-mounted stent technique to achieve a predetermined-sized fenestration of an atrial baffle in a patient with Fontan circulation. The details of the technique are described.

Adult↗
PubMed2006

Fate of bicuspid aortic valves in patients undergoing aortic root repair or replacement for aortic root enlargement.

OBJECTIVE: To better understand the outcome of the bicuspid aortic valve (BAV) after valve-sparing root replacement, we evaluated BAV function after its preservation at the time of the ascending aorta (AA) repair. PATIENTS AND METHODS: From January 1, 1994, through March 31, 2002, BAVs were preserved during repair of AA aneurysms in 21 patients (mean +/- SD age, 45+/-12 years; 13 males). We reviewed the clinical and surgical records of these patients for baseline characteristics, operative procedures, and data at latest follow-up. RESULTS: The primary indication for operation was AA enlargement (median diameter, 55 mm; range, 43-65 mm) in 18 patients and severe aortic regurgitation (AR) in 3 patients. Preoperatively, the BAV exhibited mild or moderate stenosis in 5 patients (mean gradient, 25 mm Hg; range, 19-34 mm Hg), moderate AR in 2, and severe AR in 3. Aortic valve repair was performed in 11 patients. Seventeen patients had excision and graft replacement of the enlarged AA, and 4 patients had primary AA repair. There were no perioperative deaths. Moderate or severe AR was relieved in all patients early postoperatively and during follow-up (median, 2.5 years; maximum, 7.6 years). One patient required aortic valve replacement at 4.8 years for AR. An additional patient had recurrent, severe AR but was asymptomatic and has not undergone reoperation. CONCLUSION: Repair of diseased BAVs or preservation of functionally normal BAVs during surgery for AA aneurysms has a low perioperative risk, and early results are encouraging. Additional observation is necessary to determine whether this strategy has real advantages over early aortic valve replacement.

Adolescent↗
PubMed2005

Radiofrequency perforation and conventional needle percutaneous transseptal left heart access: pathological features.

Perforating radiofrequency (PRF) energy has been used to obtain percutaneous transseptal left heart access. Contrary to ablative radiofrequency (RF), myocardial tissue responses to PRF thermal injury are incompletely defined. In this study, a newly developed RF catheter system for transseptal left atrial entry was compared with conventional needle puncture. Of 15 piglets having transfemoral cardiac catheterization, 12 had transseptal procedures. Needle punctures (NP) and PRF were followed by acute (1 hr; 3 NP, 3 PRF) and chronic necropsy (1 month; 3 NP, 3 PRF). The remaining three piglets had intentional RF aortic perforation through the atrial roof with necropsy at 1 month. Gross and histopathological effects were examined. Acutely, the gross RF lesion was similar to needle puncture. Histologically, the RF lesions had minimal mural thrombus, an inner zone of thermal injury characterized by grayish cytoplasmic staining (elastic trichrome), and a bubbly transformation of the cytoplasm in innermost cardiomyocytes, partial persistence of cross-striations, and an acute inflammatory reaction. The outer extent of the lesion (< 1 mm) was defined by a halo of contraction band necrosis similar to needle puncture. Acute NP injury showed comparable depth and extent of myocyte necrosis (principally contraction bands) with adjacent tissue hemorrhage and edema. At 1 month, a well-developed densely collagenous scar was present in both aortic and transseptal PRF lesions. The extent of acute RF injury is similar to that seen in conventional NP, but the characteristics of tissue insult are different. Both show well-developed healing at 1 month.

Animals↗
PubMed2005

Neonatal aortic stenosis.

Neonatal aortic stenosis is a complex and heterogeneous condition, defined as left ventricular outflow tract obstruction at valvular level, presenting and often requiring treatment in the first month of life. Initial presentation may be catastrophic, necessitating hemodynamic, respiratory and metabolic resuscitation. Subsequent management is focused on maintaining systemic blood flow, either via a univentricular Norwood palliation or a biventricular route, in which the effective aortic valve area is increased by balloon dilation or surgical valvotomy. In infants with aortic annular hypoplasia but adequately sized left ventricle, the Ross-Konno procedure is also an attractive option. Outcomes after biventricular management have improved in recent years as a consequence of better patient selection, perioperative management and advances in catheter technology. Exciting new developments are likely to significantly modify the natural history of this disorder, including fetal intervention for the salvage of the hypoplastic left ventricle; 3D echocardiography providing better definition of valve morphology and aiding patient selection for a surgical or catheter-based intervention; and new transcutaneous approaches, such as duel beam echo, to perforate the valve.

Aorta↗
PubMed2004

Outcomes of pregnancy in women with tetralogy of Fallot.

OBJECTIVES: We sought to determine pregnancy outcomes in patients with tetralogy of Fallot (TOF). BACKGROUND: Pregnancy outcomes in patients with TOF are incompletely defined. METHODS: Clinical, hemodynamic, and obstetric data were reviewed for women with TOF and prior pregnancy. RESULTS: Of 72 respondents, 43 (mean age, 26 years) had 112 pregnancies (range, 1 to 5); 82 pregnancies were successful. Eight women had unrepaired TOF at the time of their 20 successful pregnancies. At first assessment (age > or =18 years), six patients had pulmonary hypertension, three had moderate or severe right ventricular (RV) systolic dysfunction, and 13 had severe RV dilation due to pulmonic regurgitation. Sixteen patients had 30 miscarriages (27%) and one term stillbirth. Mean overall birth weight was 3.2 kg (range, 2.1 to 4.2 kg). Unrepaired TOF (p = 0.05) and morphologic pulmonary artery abnormality (p = 0.03) were independently predictive of infant birth weight. Six patients had cardiovascular complications during pregnancy: supraventricular tachycardia in two, heart failure in two, pulmonary embolism in a patient with pulmonary hypertension, and progressive RV dilation in a patient with severe pulmonic regurgitation. Five infants (6%) had congenital anomalies. CONCLUSIONS: Patients with TOF have an increased risk of fetal loss, and their offspring are more likely to have congenital anomalies than offspring in the general population. Adverse maternal events, although rare, may be associated with left ventricular dysfunction, severe pulmonary hypertension, and severe pulmonic regurgitation with RV dysfunction.

Adult↗
PubMed2004

Successful percutaneous ablation of ventricular tachycardia in congenitally corrected transposition of the great arteries, a case report.

Ventricular tachycardia (VT) is rarely recognized in patients with congenitally corrected transposition of the great arteries (CCTGA). We describe a 48-year-old woman with CCTGA, systemic atrioventricular valve replacement for Ebsteinoid malformation of the valve, ventricular dysfunction and ventricular tachycardia related to the previous surgical scar. The patient had successful non-contact mapping and radiofrequency ablation of the offending tachycardia substrate.

Cardiac Pacing, Artificial↗
PubMed2004

Radiofrequency applications in congenital heart disease.

The relatively recent application of radiofrequency technologies in the treatment of congenital heart defects has provided a safe and effective alternative to conventional therapies in establishing endovascular patency for a variety of lesions. Radiofrequency, with typically used frequencies of approximately 500 kHz, does not cause pain and is unlikely to induce atrial or ventricular fibrillation. It can be used either to ablate (higher power (35-50 W); longer duration of application (90-120 sec); lower voltage (30-50 V)) or to perforate (lower power (5-10 W) shorter duration of application (1-5 sec), higher voltage (150-280 V)). In the past, perforating radiofrequency has been applied to establish right ventricular outflow tract patency in pulmonary atresia with intact septum and with ventricular septal defect. More recently radiofrequency has been shown to be effective at recanalizing central and peripheral vasculature and has also been applied in establishing percutaneous left heart access. A new radiofrequency catheter, dedicated to transseptal left atrial cannulation, has been demonstrated to be safe and effective in an animal model and is now ready for clinical trials.

Adolescent↗
PubMed2003

Pressure half-time predicts hemodynamically significant pulmonary regurgitation in adult patients with repaired tetralogy of fallot.

Pulmonary regurgitation (PR) is associated with adverse outcomes late after tetralogy of Fallot repair. Accurate assessment of PR in these patients is, therefore, fundamental to their clinical treatment; however, accurate ultrasound markers of severity are as yet poorly defined. This is a prospective study of 34 adult patients with repaired tetralogy of Fallot. Cardiac magnetic resonance imaging was used to assess the PR fraction and its hemodynamic significance on the right ventricular volumes. Regurgitant fractions >/= 20% were associated with significant increases in right ventricular end-diastolic volumes. Echocardiographic continuous wave Doppler profiles of the PR jet were used to calculate pressure half-time. Pulmonary pressure half-time < 100 milliseconds was found to be a good indicator of hemodynamically significant regurgitation. This measure is highly reproducible and easily accessible.

Adult↗