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W A Devine

Publications and source records attributed to W A Devine.

At least 19 recordsLinked to original sources
PubMed2001

Attenuation of interatrial conduction using right atrial septal catheter ablation.

OBJECTIVES: We sought to characterize a method of attenuating interatrial conduction using radiofrequency ablated lesions applied to the right atrial septum. BACKGROUND: Interatrial conduction occurs in specific zones. Recent data suggest that interatrial conduction can be important in triggering and sustaining atrial fibrillation. Therefore, a method for attenuating interatrial conduction may have therapeutic value. METHODS: In 13 healthy pigs, interatrial conduction was evaluated before and after sequential ablation of the right atrial septum, targeting interatrial conduction zones. In six animals, zone 1 (crista terminalis and limbus) was ablated first, followed by ablation of zone 2 (fossa ovalis and coronary sinus ostium). In the other seven animals, the order of ablation was reversed. Electrophysiologic and pathologic findings were correlated. RESULTS: After ablation of zone 1, interatrial conduction was slowed, but there was no block. After ablation of zone 2, conduction was unchanged. After ablation of both zones, complete block was observed in four animals, and there was left atrial quiescence. In the remaining nine animals, incomplete block was observed, with marked conduction slowing or block during sinus rhythm and pacing. Ablation did not adversely affect atrioventricular node conduction, nor did it facilitate sustenance of an atrial arrhythmia. Pathologic analysis revealed that complete interatrial conduction block was associated with confluent ablation of both targeted zones. CONCLUSIONS: Catheter ablation of the right atrial septum attenuated interatrial conduction without disturbing atrioventricular conduction.

Animals↗
PubMed2001

Linear ablation using an irrigated electrode electrophysiologic and histologic lesion evolution comparison with ablation utilizing a non-irrigated electrode.

OBJECTIVES: To characterize the electrophysiologic and histologic sequelae of linear atrial ablation utilizing an irrigated electrode. To compare "irrigated" lesions with lesions deployed using the same electrode in a non-irrigated mode. BACKGROUND: Previous reports of radiofrequency catheter ablation using an irrigated electrode have emphasized its favorable effect on lesion depth. We hypothesized that electrode irrigation would also benefit linear ablation of smooth atrial myocardium, a relatively superficial target. METHODS: In healthy pigs, lesions were deployed in the right and left atria. Acutely, lesions resulting from ablation using an irrigated electrode, with radiofrequency energy titration guided by electrogram amplitude reduction, were compared to lesions using the same electrode without irrigation, with energy titration guided by electrode thermometry. Irrigated lesions were also assessed serially. RESULTS: Acutely, irrigated lesions formed complete conduction barriers and were uncomplicated. In contrast, non-irrigated lesions formed complete conduction barriers but were frequently complicated, exhibiting endocardial charring, barotrauma, and pericardial damage. The rate and pattern of histologic evolution of irrigated lesions were uniform throughout each lesion; right and left atrial lesions healed similarly. During healing, 90 % of lesions remained complete conduction barriers and 10 % manifested single discrete conduction gaps where viable appearing myocytes bridged the lesion. CONCLUSIONS: Complete, uncomplicated linear lesions could be reliably deployed in either atrium with an irrigated electrode. Not all lesions remained complete barriers to conduction during their histologic evolution. Lesions deployed with the same electrode in a non-irrigated mode were complete but frequently complicated.

Animals↗
PubMed2001

Cardiac swelling associated with linear radiofrequency ablation in the atrium.

OBJECTIVES: To characterize myocardial swelling in response to application of endocardial radio-frequency ablation lesions. BACKGROUND: In individual patients, we have observed that ablation in the posterior right atrium was associated with echocardiographic evidence of atrial and contiguous right pulmonary vein wall swelling. METHODS: 1. Human Subjects: "linear" ablation was performed in the posterior right atrium in 10 subjects; a portion of the ablation lesion was contiguous to the right pulmonary vein; this area was defined as the "contiguity zone". In the contiguity zone, right atrial wall thickness and pulmonary vein lumen diameter were measured utilizing intracardiac echocardiography. Measurements were made just prior to (baseline) and immediately after ablation.2. Porcine Subjects: linear ablation was performed in the posterior right atrium of 14 pigs. In the contiguity zone, atrial wall thickness, interstitial space thickness, right pulmonary vein wall thickness and lumen diameter were measured using intracardiac echocardiography. Measurements were made at baseline, immediately after ablation, and at 1, 4, 8 or 12 weeks after ablation (followup). Post-mortem pathologic evaluation of the contiguity zone was performed. RESULTS: 1. Human Subjects: Immediately after ablation, relative to baseline right atrial wall thickness was significantly increased (9.4+/-3.1mm versus 5.4+/-1.5 mm) and right pulmonary vein lumen diameter was significantly decreased (6.2+/-2.9 mm versus 8.1+/-2.9 mm).2. Porcine Subjects: Immediately after ablation, right atrial wall thickness (4.1+/-1.2 mm), interstitial space thickness (1.9+/-1.1mm), and right pulmonary vein wall thickness (1.2+/-0.4 mm) were each significantly increased relative to baseline (1.0+/-0.3 mm, 0+/-0 mm, and 0.7+/-0.2 mm, respectively) and pulmonary vein lumen diameter was significantly decreased (5.0+/-1.4 mm versus 6.9+/-2.2 mm). Similar findings were made at the 1 week followup interval. At 4, 8 and 12 week followup intervals, thicknesses and lumen diameter were not significantly different from baseline. At post-mortem examination, direct measurements of wall thickness were significantly correlated with echocardiographic measurements. Histologic analysis demonstrated edema to be the cause of the early wall thickness and lumen diameter changes. Ablation lesions were transmural in the right atria of all animals; in some animals, lesion formation was also observed in the pulmonary vein wall. CONCLUSIONS: Cardiac edema resulting from right atrial linear ablation results in swelling of atrial and contiguous right pulmonary vein walls, as well as the interposed extracardiac interstitial space. These changes are associated with a decrease in pulmonary vein lumen diameter. Swelling evolves rapidly and resolves within 4 weeks.

Adult↗
PubMed2001

An approach to dissecting the congenitally malformed heart in the forensic autopsy: the value of sequential segmental analysis.

The demonstration of congenital heart disease at autopsy necessitates the careful preservation and examination of the heart, the vessels, and their connections. Techniques preserving these connections and using a reproducible and systematic approach are preferred. The Rokitansky method of organ block dissection, in combination with a system of heart examination termed sequential segmental analysis, provides such an approach. This study is based on the examination of heart specimens accessioned into the Frank E. Sherman, M.D., and Cora C. Lenox, M.D., Heart Museum (containing approximately 2400 specimens) of the Pathology Department, Children's Hospital of Pittsburgh. Specimens received in consultation during a 25-year period from hospitals and coroners'/medical examiners' offices were examined, and the corresponding reports were reviewed. Of 46 total heart specimens examined (1975-1999), 29 (63%) were dissected properly or left intact for dissection at Children's Hospital of Pittsburgh, and 17 (37%) were incorrectly dissected for the demonstration of congenital heart disease. Of these 17 cases, 11 (24%) displayed dissection errors, which did not hinder a complete diagnosis, 3 cases (6.5%) had errors that enabled only an incomplete diagnosis, and in 3 cases (6.5%), no diagnosis of congenital heart disease could be made. Dissection mistakes and means of avoiding them are discussed. Review of medical and family history, external and internal examination, and a reproducible and sequential method of examining the heart and its connections enables documentation of even the most complex cardiovascular anomalies.

Autopsy↗
PubMed1998

Morphometric analysis of atrioventricular septal defect with common valve orifice.

OBJECTIVES: We sought to analyze morphometric features of atrioventricular septal defect (AVSD) in autopsy specimens and to consider the developmental implications of obstruction in either ventricular outflow tract. BACKGROUND: Left ventricular outlet obstruction (LVO) is more prevalent in patients with Rastelli type A morphology. When tetralogy of Fallot (ToF) complicates this malformation, there is usually a free-floating superior bridging leaflet. The reasons for these associations are uncertain. METHODS: In 133 hearts with AVSD and common atrioventricular (AV) valve orifice, we measured the degrees of horizontal and anterior deviation of the great arteries from the AV valve, the diameters of the ventricular outlets and the great arteries and the degree of deficiency of the ventricular septum. RESULTS: In Rastelli type A morphology, the great arteries were deviated more leftward than in type C morphology (p < 0.01). Type A hearts also had a relatively small aorta, with a long and narrow subaortic tract. The presence of obstruction in either ventricular outlet was associated with a more oblique arrangement of the great arteries, with the pulmonary trunk being more leftward than in hearts without LVO (p < 0.01). In combination with ToF, the aorta was dextroposed and the pulmonary trunk was located more posteriorly (p < 0.01). No heart with type A morphology showed ToF (p < 0.01). CONCLUSIONS: The geometric arrangement of the great arteries correlated significantly with obstruction in either ventricular outflow tract and with the Rastelli subtypes. Malrotation of the developing outlet septum may be an embryologic factor producing obstruction, with horizontal deviation of the outlets also influencing the morphology of the superior bridging leaflet.

Aorta↗
PubMed1996

Surgical anatomy of the coronary circulation in hearts with discordant atrioventricular connections.

We examined the arrangement of the coronary arterial and cardiac venous systems in 46 specimens with discordant atrioventricular connections so as to identify any structural abnormalities and to consider their surgical implications in terms of anatomical biventricular repair. Grossly abnormal arterial courses were seen in 11 hearts (24%). A substantial branch supplying the morphologically right ventricular outflow tract, which could restrict a ventriculotomy, was found in 61% of cases. The coronary sinus received all the morphologically right ventricular veins, as well as the posterior interventricular vein, in 40 hearts, this pattern being in contrast to the pattern in the normal heart. The morphologically left ventricular and anterior interventricular veins, all of which drain via the coronary sinus in the normal heart, were frequently connected independently to the morphologically right atrium in the specimens with discordant connections, the drainage occurring through the spaces between the pectinate muscles. These direct drainages are at risk of potential damage either by extensive intra-atrial maneuvers or by postoperative intraatrial thrombosis. It is predicted, therefore, that surgical results can be improved still further when account is taken of this vascular anatomy of the heart itself.

Cadaver↗
PubMed1995

Atrial appendages and venoatrial connections in hearts from patients with visceral heterotaxy.

BACKGROUND: Venoatrial connections are important when choosing surgical options for patients with visceral heterotaxy. The precise morphology of the atriums, however, is often obfuscated by the term "visceral heterotaxy." This morphologic study aims to clarify the features of significance to the cardiac surgeon. METHODS: We investigated 183 hearts from patients known from postmortem inspection to have so-called visceral heterotaxy. The connections of the systemic and pulmonary veins to the atriums, and the detailed morphology of the atriums, were examined in each case. RESULTS: Pectinate muscles extended bilaterally to the crux in 125 hearts determined to have isomeric morphologically right appendages. The other 58 hearts all exhibited bilaterally smooth-walled vestibules, and were diagnosed as having isomeric left appendages. Bilateral superior caval veins were frequent in both groups. The inferior caval vein was right- or left-sided with equal frequency in both groups, but was interrupted only in hearts with isomeric left appendages. The pulmonary veins connected in extraatrial fashion in 48% of cases with isomeric right appendages, whereas, most commonly, pulmonary veins were connected bilaterally to the atriums in those with isomeric left appendages (60%). CONCLUSIONS: Both the morphology of the atrial appendages and the venoatrial connections need to be distinguished to establish precise diagnoses in patients with so-called visceral heterotaxy ("splenic syndromes").

Abnormalities, Multiple↗
PubMed1995

The surgical anatomy of coronary venous return in hearts with isomeric atrial appendages.

Although absence of the coronary sinus is widely recognized in hearts with isomerism of the right atrial appendages, little attention has been paid to the fashion of the venous return from the heart itself. In this study, the arrangement of coronary venous return was investigated in 99 specimens with isomeric right and 49 with isomeric left appendages. In the normal heart, the coronary veins consist of a circumflex component within the atrioventricular groove and longitudinal components on the ventricular mass. The circumflex venous system was seen in 44 hearts with isomerism of left appendages (90%), but 23 of these hearts lacked the anatomic features of the coronary sinus. Circumflex veins were entirely lacking in the other 10% of hearts with isomeric left appendages and in all those with isomeric right appendages. In these hearts, longitudinal veins drained independently into the atria in three patterns. The first was a direct connection, with the venous orifice opening between the trabeculations of the atrial wall immediately having crossed the atrioventricular groove. The second was a crooked return, with the vein running an intramural course along the atrioventricular groove. The third was a distant connection, reaching superiorly to the smooth-walled atrial component after running an intramural course. Intramural courses were seen in 19% of the longitudinal veins, such veins being found in 62% of all hearts with no circumflex venous system. These findings, which to the best of our knowledge have never previously been recognized in detail, almost certainly have potential surgical significance.

Coronary Vessel Anomalies↗
PubMed1995

Left ventricular structures in atrioventricular septal defect associated with isomerism of atrial appendages compared with similar features with usual atrial arrangement.

In patients with isomeric atrial appendages, regurgitation of atrioventricular valves is recognized clinically as one of the risk factors that militate against successful achievement of definitive repairs. To determine whether this reflected anatomic features, we investigated 91 specimens with atrioventricular septal defect that had a common atrioventricular valve and biventricular atrioventricular connections. Of these specimens, 35 had isomeric right appendages, 23 showed isomeric left appendages, and 33 had usual atrial arrangement. We measured either the size or location of the supporting papillary muscles and the circumference of the mural leaflet within the morphologically systemic ventricle, as well as the length of outlet, inlet, and so-called scooped dimensions of the muscular ventricular septum. Presence of a solitary papillary muscle, or deviation of the attachments of the papillary muscles, was more frequent in hearts with isomeric right appendages. Values for the diameter and lengths of the papillary muscles were significantly smaller in hearts with isomeric right appendages compared with those with usual atrial arrangement (p < 0.001), as were the distances between the papillary muscles (p < 0.002) and the circumference of the mural leaflet (p < 0.001). The proportional length of ventricular outlet was longer in the setting of isomeric right appendages than in the other groups (p < 0.001), whereas the extent of septal scooping showed no differences among these three groups. We conclude that these structural features could be factors in the known insufficiency of the common atrioventricular valve and the ventricular dysfunction in patients with isomeric right appendages.

Heart Atria↗
PubMed1991

The myth of the aortic annulus: the anatomy of the subaortic outflow tract.

Surgical repair of the small aortic root is limited in part by the very structure of the outflow tract from the left ventricle. The root is not constructed on the basis of a ringlike annulus supporting the leaflets of the aortic valve. The only truly circular structure within the outflow tract is the junction of the aortic wall with the underlying ventricular structures, themselves partly muscular and partly fibrous. This circular ventriculoarterial junction is crossed by the semilunar attachments of the leaflets of the aortic valve, producing an interlinking arrangement between the expanded aortic sinuses and three triangles of fibrous tissue placed beneath the apexes of the commissures between the valve leaflets. The triangles form extensions of the left ventricle that are related, in part, to the pericardial cavity surrounding the heart. The arrangements of the attachment of the leaflets in malformed valves with two (or only one) effective leaflets are highly abnormal, although these valves are usually produced on the template of three aortic sinuses. The valve with two leaflets rarely gives problems during childhood. In valves producing "critical stenosis", there is usually only one effective leaflet, a condition due to incomplete liberation of two of the anticipated three commissures. Detailed study shows that, in these malformed hearts, the attachment of the leaflets is much more annular than in normal valves, with inadequate formation of the fibrous triangles.

Aortic Valve↗
PubMed1991

The surgical anatomy of tetralogy of Fallot with pulmonary atresia rather than pulmonary stenosis.

We examined the pertinent surgical features of the anatomy of 56 hearts having tetralogy of Fallot with pulmonary atresia instead of stenosis, or malformations with pulmonary atresia closely related to tetralogy. We took particular cognizance of the pulmonary arterial supply in 15 hearts in which this was derived through systemic-to-pulmonary collateral arteries, dissecting, as far as possible, the bronchopulmonary segmental distribution of the collateral arteries compared to the intrapericardial pulmonary arteries in 11 of these hearts. Two of the hearts had absence of intrapericardial pulmonary arteries, so that a solitary arterial trunk left the base of the heart. Evidence of an atretic subpulmonary infundibulum was found in 40 of the hearts, while such an infundibulum was lacking in the remainder. The pulmonary atresia was muscular in 43 hearts, valvar in 11, while the pulmonary trunk was absent in the other two hearts. In the hearts with collateral arteries, on average 2.6 collaterals were found in each case, varying from two to five per case. Only one of these arose from a brachiocephalic artery, the others all arising from the descending aorta. The distribution of collateral arteries in two cases was remarkably reminiscent of the arrangement of bronchial arteries. As far as could be judged, 16.5 bronchopulmonary segments on average were supplied in each heart, 5.1 exclusively by collateral arteries, 11.8 by intrapericardial pulmonary arteries and an average of 0.64 segments per case having a shared supply.

Collateral Circulation↗
PubMed1990

Abnormalities of the spleen in relation to congenital malformations of the heart: a survey of necropsy findings in children.

A series of 1042 reports of necropsies on children dying at Children's Hospital of Pittsburgh was reviewed. In each case, note was taken of the status of the spleen, the lobation of the lungs, the arrangement of the bronchi, the morphology of the atrial appendages, and the presence of any congenital malformations of the heart and great vessels and of any malformations of the abdominal organs. There was isomerism of the left atrial appendages in eight (0.77%), 13 (1.25%) showed isomerism of the right appendages, and seven (0.67%) had multiple spleens without having isomerism of the atrial appendages. Unexpectedly, a normal spleen was found in one patient with isomerism of the right appendages and also in a patient with isomerism of the left appendages. In one patient with isomeric left atrial appendages there was no spleen. The review showed that the morphology of the atrial appendages, and hence the arrangement of the atria, is not accurately predicted by the type of spleen. The arrangement of the atrial appendages is the most reliable guide to the recognised combinations of congenital cardiac malformations previously described as "splenic syndromes". Because there is no certain way of predicting all the malformations in patients with complex congenital heart disease, it is advisable to record separately for each patient the details of lobation of the lungs, the bronchial and atrial arrangement, anomalies of the heart and great vessels, the type of spleen, and any abnormal arrangement of the abdominal organs.

Abnormalities, Multiple↗