Search PubMed⌕ Search

Biomedical subjects

Donald J Hagler

Publications and source records attributed to Donald J Hagler.

At least 19 recordsLinked to original sources
PubMed2007

Transcatheter closure of ischemic and post-traumatic ventricular septal ruptures.

Post-traumatic ventricular septal defects (VSD) can occur after acute MI or iatrogenically after invasive surgical procedures. Emergency surgery is associated with high perioperative mortality and postsurgical shunt in up to 20% of patients. Transcatheter closure (TCC) of post MI VSD may be an alternative that avoids the high risk of surgery. We report a lower mortality and morbidity than surgical closure in the post infarction VSD's even with a short interval between defect occurrence and percutaneous device placement. Furthermore, in patients with a failed or suboptimal surgical result adjunctive percutaneous closure may be beneficial and offers an alternative to redo VSD repair. Finally, in patients who suffer an unexpected traumatic VSD post surgical procedure, percutaneous closure offers an alternative with excellent results.

Adult↗
PubMed2006

Smoothing and cluster thresholding for cortical surface-based group analysis of fMRI data.

Cortical surface-based analysis of fMRI data has proven to be a useful method with several advantages over 3-dimensional volumetric analyses. Many of the statistical methods used in 3D analyses can be adapted for use with surface-based analyses. Operating within the framework of the FreeSurfer software package, we have implemented a surface-based version of the cluster size exclusion method used for multiple comparisons correction. Furthermore, we have a developed a new method for generating regions of interest on the cortical surface using a sliding threshold of cluster exclusion followed by cluster growth. Cluster size limits for multiple probability thresholds were estimated using random field theory and validated with Monte Carlo simulation. A prerequisite of RFT or cluster size simulation is an estimate of the smoothness of the data. In order to estimate the intrinsic smoothness of group analysis statistics, independent of true activations, we conducted a group analysis of simulated noise data sets. Because smoothing on a cortical surface mesh is typically implemented using an iterative method, rather than directly applying a Gaussian blurring kernel, it is also necessary to determine the width of the equivalent Gaussian blurring kernel as a function of smoothing steps. Iterative smoothing has previously been modeled as continuous heat diffusion, providing a theoretical basis for predicting the equivalent kernel width, but the predictions of the model were not empirically tested. We generated an empirical heat diffusion kernel width function by performing surface-based smoothing simulations and found a large disparity between the expected and actual kernel widths.

Cerebral Cortex↗
PubMed2006

Right ventricular function in asymptomatic individuals with a systemic right ventricle.

BACKGROUND: In congenital heart defects where the morphologic right ventricle (RV) supports the systemic circulation, RV failure is common yet develops gradually. We hypothesized that patients who are asymptomatic may have unrecognized RV dysfunction. METHODS: Conventional and Doppler tissue/strain echocardiography were performed on consecutive patients with asymptomatic systemic RV caused by congenitally corrected transposition of the great arteries (ccTGA) and on age-matched control subjects. RV index of myocardial performance was measured using conventional echocardiography. Longitudinal tissue velocities, strain rate, and strain of the basal RV free wall were measured using Doppler tissue/strain echocardiography and compared with nonsystemic RV of the control subjects. RESULTS: Mean age was 39.5 +/- 14.6 (n = 13) and 36 +/- 24 (n = 10) years for ccTGA and control groups, respectively. Mean RV index of myocardial performance was higher in patients with ccTGA than in control subjects (0.66 +/- 0.25 vs 0.28 +/- 0.12, P < .001). Mean RV tissue displacement (10.8 +/- 4.5 vs 20.3 +/- 3.9 mm, P < .0001), peak systolic strain rate (-1.16 +/- 0.3 vs -2.23 +/- 0.9 s(-1), P = .005), and peak systolic strain (-17.3 +/- 8.0 vs -30.6 +/- 11.0%, P = .008) were significantly lower in patients with ccTGA compared with control subjects, respectively. CONCLUSION: Patients with asymptomatic ccTGA have quantifiable RV dysfunction by echocardiography.

Adult↗
PubMed2006

Isolated supravalvular pulmonary artery ridge in a 70-year-old man.

Transthoracic echocardiography allows noninvasive assessment of the structure and function of the great vessels of the heart. We report a case of a 70-year-old man who had an isolated, mildly obstructive, supravalvular pulmonary artery ridge that was detected incidentally with transthoracic echocardiography. This report confirms the utility of transthoracic echocardiography in the detection of this condition and discusses quantification of this rare anomaly.

Aged↗
PubMed2006

Paradoxical emboli in children and young adults: role of atrial septal defect and patent foramen ovale device closure.

OBJECTIVE: To describe a multicenter experience with patent foramen ovale (PFO) and atrial septal defect (ASD) device closure for presumed paradoxical emboli in children and young adults (<35 years old). PATIENTS AND METHODS: Medical records were reviewed of patients who had device closure of an ASD or PFO, who were younger than 35 years, and who had a history of presumed paradoxical embolus between January 1999 and August 2005 at Mayo Clinic, Rochester, Minn, University of Parma, Parma, Italy, and Loyola University Medical Center, Maywood, Ill. RESULTS: Forty-five patients fulfilled the inclusion criteria. Median patient age was 29.0 years (range, 5.0-34.9 years), and 23 patients (51%) were male. Clinical diagnoses included the following: stroke, 30 (67%); transient ischemic attack, 13 (29%); myocardial infarction, 1 (2%); and renal infarct, 1 (2%). Overall, 42 patients (93%) had a PFO, and 3 (7%) had an ASD. Seventeen patients had known cardiovascular disease risk factors: tobacco use (10 patients), hypercoagulable states (7 patients), systemic hypertension (3 patients), and hyperilpidemia (2 patients). No major procedural complications occurred. Median follow-up evaluation was performed at 5.3 months (range, 2.5-40.0 months). Forty-four patients (98%) had no recurrent neurologic events and no residual atrial shunt by contrast transthoracic echocardiography. CONCLUSIONS: Cryptogenic ischemic events occur in young patients and have serious sequelae. The potential for paradoxical embolization through a PFO or an ASD should be assessed in all such patients. In our short-term follow-up, device closure was a safe alternative therapeutic option for children and young adults with presumed paradoxical emboli.

Adolescent↗
PubMed2005

Spatial maps in frontal and prefrontal cortex.

Though the function of prefrontal cortex has been extensively investigated, little is known about the internal organization of individual prefrontal areas. Functional magnetic resonance imaging was used to show that some frontal and prefrontal cortical areas represent visual space in orderly, reproducible, topographic maps. The map-containing areas partly overlap dorsolateral prefrontal areas engaged by working memory tasks. These maps may be useful for attending to task-relevant objects at various spatial locations, an aspect of the executive control of attention.

Adult↗
PubMed2005

Percutaneous closure of left ventricular-to-right atrial fistula after prosthetic mitral valve rereplacement using the Amplatzer duct occluder.

A 70-year-old female with a history of rheumatic heart disease underwent rereplacement of mitral valve mechanical prosthesis in May 2003. Seven months later, she presented with progressive exertional dyspnea, exercise intolerance, and a new holosystolic/diastolic murmur. Echocardiography confirmed a large shunt through a fistula in the inferior limbus of the atrial septum with left ventricular-to-right atrial communication. We report the novel use of the Amplatzer duct occluder for closure of the fistulous tract.

Aged↗
PubMed2005

Double outlet right ventricle: opinions regarding management.

In the current era of superb surgical results for congenital heart disease, several management options are available for patients born with double outlet right ventricle (DORV). The surgical repair of DORV is tailored to address the variety of abnormalities associated with this lesion. The treatment strategies are dependent upon the anatomy and relationship of the ventricular septal defect (VSD) and the great arteries. For patients with subaortic or doubly committed VSDs, without right ventricular outflow tract obstruction, the usual repair is an intraventricular tunnel from the VSD to the aorta. If right ventricular outflow tract obstruction exists, then augmentation of the right ventricular outflow tract or conduit placement from the right ventricle to the pulmonary artery is necessary. For the "Taussig-Bing anomaly" (subpulmonary VSD) an arterial switch operation is indicated with tunneling of the VSD to the neoaorta. For patients with a remote VSD, complex atrioventricular valve abnormalities, or unbalanced ventricles, a staged palliative approach is warranted. This approach will result in the patient having "single ventricle" physiology, and "Fontan anatomy" after the staging surgeries. Outcomes are determined by the surgery performed. Patients who require conduit placement from right ventricle to pulmonary artery will need subsequent surgery for replacement of the conduit. Complex intraventricular tunnels are at risk for developing subaortic obstruction. Patients who had arterial switch operations have thus far had excellent results. However, these patients may be at risk for development of neoaortic valve regurgitation requiring subsequent reoperation. Complex biventricular intracardiac repairs have been associated with a higher risk of reoperation. In the past 10 to 15 years, patients undergoing Fontan operations have had improved early and late survival. However, long-term problems after the Fontan operation include arrhythmia and development of protein-losing enteropathy.

Journal Article↗
PubMed2005

Echocardiographic assessment of isolated pulmonary valve stenosis: which outpatient Doppler gradient has the most clinical validity?

Maximum instantaneous Doppler gradient has been the primary variable used to assess severity of pulmonary valve stenosis. However, recent observations suggest that outpatient maximum Doppler gradient often overstates clinical severity, as measured by catheter peak-to-peak gradient (PPG). This study sought to determine which outpatient Doppler gradient was most predictive of subsequently measured PPG. Ninety patients were included. Outpatient mean Doppler gradient showed the best correlation and agreement with the catheter PPG (r = 0.82, bias = -5 mm Hg). Maximum Doppler gradients, even when corrected for proximal velocity, consistently overestimated the PPG (bias = +21-26 mm Hg). Outpatient mean gradient was most predictive of subsequent PPG and should be used to determine whether to intervene for patients with isolated pulmonary valve stenosis. Use of only the maximum Doppler gradient to assess pulmonary valve stenosis will lead to a systematic overstatement of the severity of the stenosis.

Adolescent↗
PubMed2005

Outpatient echocardiographic assessment of complex pulmonary outflow stenosis: Doppler mean gradient is superior to the maximum instantaneous gradient.

Evaluation of pulmonary outflow obstruction has focused on maximum instantaneous gradient (MIG). However, experience suggests that outpatient Doppler MIG often overstates the degree of stenosis. In this study of 132 patients with complex pulmonary stenosis, the mean Doppler gradient showed superior correlation and agreement with invasive peak-to-peak gradient (PPG) (r = 0.91, bias = -6 mm Hg). Agreement between mean gradient and PPG remained excellent for patients with prosthetic conduits (bias = -4 mm Hg). When PPG was 50 mm Hg more, both mean Doppler gradient and MIG corrected for prevalve velocity provided reasonable estimates of PPG (bias = -13 and +17 mm Hg, respectively). Uncorrected MIG remained significantly greater than PPG (bias = +27 mm Hg). Outpatient MIG consistently overstated subsequent PPG. In unselected patients with conduits or with PPG of 50 mm Hg or less, mean Doppler gradient provided the best prediction of PPG. These data provide a strong argument for the routine use of mean gradients in complex pulmonary stenosis.

Adolescent↗
PubMed2004

Point-light biological motion perception activates human premotor cortex.

Motion cues can be surprisingly powerful in defining objects and events. Specifically, a handful of point-lights attached to the joints of a human actor will evoke a vivid percept of action when the body is in motion. The perception of point-light biological motion activates posterior cortical areas of the brain. On the other hand, observation of others' actions is known to also evoke activity in motor and premotor areas in frontal cortex. In the present study, we investigated whether point-light biological motion animations would lead to activity in frontal cortex as well. We performed a human functional magnetic resonance imaging study on a high-field-strength magnet and used a number of methods to increase signal, as well as cortical surface-based analysis methods. Areas that responded selectively to point-light biological motion were found in lateral and inferior temporal cortex and in inferior frontal cortex. The robust responses we observed in frontal areas indicate that these stimuli can also recruit action observation networks, although they are very simplified and characterize actions by motion cues alone. The finding that even point-light animations evoke activity in frontal regions suggests that the motor system of the observer may be recruited to "fill in" these simplified displays.

Adult↗
PubMed2004

Patent foramen ovale in cryptogenic stroke: current understanding and management options.

There is increasing interest in the association between patent foramen ovale (PFO) and documented stroke of unknown cause, commonly referred to as cryptogenic stroke. We reviewed the literature and, on the basis of the available data, designed a diagnostic and treatment algorithm for patients with PFO and cryptogenic stroke. Patent foramen ovale is relatively common in the general population, but its prevalence is higher in patients with cryptogenic stroke. Importantly, paradoxical embolism through a PFO should be strongly considered in young patients with cryptogenic stroke. There is no consensus on the optimal management strategy, but treatment options include antiplatelet agents, warfarin sodium, percutaneous device closure, and surgical closure. High-risk features in the patient's history (ie, temporal association between Valsalva-inducing maneuvers and stroke, coexisting hypercoagulable state, recurrent strokes, and PFO with large opening, large right-to-left shunt, or right-to-left shunting at rest, and a coexisting atrial septal aneurysm) should prompt PFO closure.

Adult↗
PubMed2004

Thrombosis after septal closure device placement: a review of the current literature.

Thrombus formation has been described for all types of commercially available transcatheter septal occlusion devices. Most reports have been single-institution case studies. Screening for hypercoagulable conditions prior to device placement and anticoagulation after device deployment has been variable. The objective of this study was to synthesize the current experience with device thrombosis; the Medline database from 1980 until 2004 was searched. Seventeen articles identified 54 unique patients with device thrombosis. Thrombus developed on eight different types of transcatheter devices. All commercially available devices had at least one reported case of thrombosis. Patient mean age was 44.2 +/- 9.8 years. Thrombosis was diagnosed at a mean of 5 months after device deployment. Prior to device placement, 12 patients had normal coagulation evaluations and 5 had coagulopathies. For 37 patients, no mention was made in the report of coagulation studies. Prior to device thrombosis, 26 patients received aspirin and clopidogrel, 15 patients received aspirin alone, 8 received warfarin, 2 heparin alone, 1 aspirin and warfarin. One patient with hemophilia A received no anticoagulation and in one case treatment prior to thrombosis was not reported. After device thrombosis, 35 patients were treated with warfarin with thrombus resolution, 2 had successful lytic therapy, 1 was treated with heparin alone. Sixteen patients had surgical explantation of the device. Septal occlusion device thrombosis is rare. All types of commercially available devices have been associated with thrombosis. All patients should have early (< or = 3 months) echocardiographic surveillance for device thrombosis. Thorough coagulation evaluation is imperative prior to transcatheter device placement.

Adult↗
PubMed2004

Acute myocardial infarction in a child: possible pathogenic role of patent foramen ovale associated with heritable thrombophilia.

We report an 8-year-old girl who presented with clinical features of an acute myocardial infarction. The angiographic appearance of the coronary arteries was normal. A thrombophilic state caused by a homozygote genotype for the prothrombin G20210A mutation was detected, and a patent foramen ovale (PFO) with right-to-left shunting after Valsalva maneuver was demonstrated by transesophageal contrast echocardiography. No other embolic source was identified. We suggest that paradoxical embolization through a PFO resulted in a myocardial infarction in this young patient with hereditary thrombophilia. We closed the patient's PFO with a 25-mm PFO occluder. She was anticoagulated with warfarin for 6 months. After 6 months, a contrast echocardiogram showed no evidence of residual atrial shunt. There has been no evident recurrent paradoxical embolization.

Child↗
PubMed2004

Intracardiac echocardiographic guidance during transcatheter device closure of atrial septal defect and patent foramen ovale.

OBJECTIVES: To describe our experience with intracardiac echocardiographic (ICE) guidance during transcatheter device closure of atrial septal defect (ASD) and patent foramen ovale (PFO) and to describe a detailed stepwise approach for performing ICE examinations. PATIENTS AND METHODS: We reviewed the ICE results of all patients who underwent transcatheter device closure of ASD/PFO at the Mayo Clinic in Rochester, Minn, between October 2000 and November 2002. Conscious sedation was used, and all ICE studies were performed using a diagnostic ultrasound catheter. RESULTS: Ninety-four patients (47 male; median age, 51 years [range, 17-81 years]) underwent ICE during transcatheter device closure of ASD/PFO. Total procedure time was 128 minutes (range, 27-320 minutes). ICE identified a previously unrecognized anatomical diagnosis in 32 of 94 patients. An additional ASD or PFO was found in 16 patients; a redundant atrial septum or an atrial septal aneurysm was found in 12 patients. There were few ICE complications (4%): 3 patients developed atrial fibrillation, and 1 developed supraventricular tachycardia; of these 4, 2 resolved spontaneously, and 2 required cardioversion with no recurrence. CONCLUSION: ICE provides anatomical detail of ASD/PFO and cardiac structures facilitating congenital cardiac interventional procedures. ICE eliminates major drawbacks related to the use of transesophageal echocardiographic guidance for transcatheter device closure of ASD/PFO, specifically problems related to airway management. Finally, ICE gives the interventional cardiologist the ability to control all aspects of imaging without relying on additional echocardiographic support. We believe that ICE should be considered the preferred imaging technique for guidance of transcatheter device closure of ASD/PFO in adults and larger pediatric patients.

Adolescent↗
PubMed2004

Transcatheter Amplatzer device closure of atrial septal defect and patent foramen ovale in patients with presumed paradoxical embolism.

OBJECTIVE: To review our experience with, and profile the safety and efficacy of, the Amplatzer PFO (patent foramen ovale) occluder (APO) and Amplatzer septal occluder (ASO) used to close PFO and/or atrial septal defect (ASD) in patients with paradoxical embolism (PE). PATIENTS AND METHODS: Between April 1998 and November 2002, 103 patients at the Mayo Clinic in Rochester, Minn, and Scottsdale, Ariz, mean age 52.4 years, with presumed PE (transient ischemic attack [n=22], stroke [n=77], or peripheral emboli [n=4]) underwent transcatheter device closure of PFO (n=81), ASD (n=12), and ASD/PFO (n=10) with 106 devices (APO [n=22] or ASO [n=84]). RESULTS: All devices deployed successfully, and no patients died. Procedural complications included atrial fibrillation (n=2), vessel injury (n=3), profound sinus node dysfunction (n=1), and device embolization with successful retrieval (n=1). At 3 months, 7 of 95 monitored patients had trivial residual shunt; at 12 months, 2 of 28 monitored patients had trivial residual shunt. Three patients had recurrent events--2 transient ischemic attacks and 1 retinal artery occlusion--at a mean +/- SD follow-up of 8.3 +/- 8.1 months (range, 1-34 months). None of these 3 patients had residual shunt or evidence of intracardiac thrombus. The average annual recurrence of all events was 3.6% at 23 months. The overall mean +/- SD freedom from recurrence of all events was 98.9% +/- 1.2% and 83.8% +/- 10.2% at 12 and 29 months of follow-up, respectively. CONCLUSIONS: Transcatheter device closure of PFO and/or ASD with use of APO/ASO in patients with presumed PE is effective and safe. Recurrent events may occur in the absence of a residual shunt.

Adult↗