The histologic estimation of coronary artery stenoses: accuracy and the effect of lumen shape.

The authors have recently investigated the histologic estimation of coronary artery stenoses (CAS) to determine its reproducibility and the effect of training on reproducibility. The present study extends this work, examining the accuracy, the sensitivity, and the specificity of the estimation of CAS. Further, the effect of one histologic variable (i.e., arterial lumen shape) on the evaluation of CAS is examined. As described previously, 20 randomly selected Movat-stained coronary artery cross-sections were reviewed three times, at 3-month intervals, by six clinical pathologists (CPs), six pathology residents (Res), seven anatomic pathologists (APs), and two cardiovascular pathologists (CVPs). Before the third iteration, training in CAS assessment was provided. In the present study, for comparison with observer estimates, image analysis was used to establish the actual percent CAS and determine observer accuracy. The results of this study showed, paradoxically, that greater experience did not correlate with greater accuracy: The CPs consistently had the highest accuracy scores and the CVPs consistently had the lowest. Training, however, improved the accuracy scores of all groups. Stenotic arterial cross-sections with residual lumens showing concentric or eccentric polymorphous shapes were consistently underestimated compared to image analysis, while lumens with a eccentric slitlike shape were consistently overestimated.

Histologic estimation of coronary artery stenoses: reproducibility and the effect of training.

Histologic estimation of coronary artery stenoses (CAS) provides the 'gold-standard' for clinicopathologic correlations and medicolegal investigations, yet little evidence supports histology as a reproducible diagnostic measure, and none addresses the effect of training on its use. To study these questions, 20 randomly selected Movat-stained coronary artery cross-sections were reviewed 3 times, at 3-month intervals, by six clinical pathologists (CPs), six pathology residents (Res), seven anatomic pathologists (APs), and two cardiovascular pathologists (CVPs). Before the third iteration, a guide to CAS assessment with illustrations was provided. Inter- and intraobserver reproducibility were determined using interclass correlation coefficients (ICC) (0.40-0.75 = fair-good; > or = 0.76 = excellent agreement beyond chance). Surprisingly, all study groups had excellent interobserver reproducibility. Before training, at Time 1, the scores were CPs, 0.77; Res, 0.89; APs, 0.93; and CVPs, 0.93. After training, at Time 3, the results were CPs, 0.81; Res, 0.91; APs, 0.86; and CVPs, 0.88. Intraobserver reproducibility for CPs overall was good (ICC, 0.74), and excellent for Res, APs, and CVPs (0.89, 0.94, and 0.97, respectively). In conclusion, statistical analysis failed to demonstrate any significant effect of training or experience on observer reproducibility.

Focal and patchy cardiac valve lesions: a clinicopathological review.

Pathologists and surgeons often encounter cardiac valves with focal or patchy abnormalities either at postmortem examination or during the assessment of a valve removed at surgery. Many health professionals including nurses, cardiologists, echocardiographers, sonographers and radiologists may be called upon to assess these lesions. With the development of increasingly more sophisticated and sensitive imaging techniques, including transesophageal echocardiography and magnetic resonance imaging, more valve lesions are being discovered. Many patients with metabolic abnormalities, systemic diseases or storage disease have valvular findings. Some are characteristic and distinctive for the specific disease, while others are seen in numerous diseases. Most patients develop age-related valvular changes, and these are more frequently encountered with the aging population. A practical approach the health professional should take to assess these valve lesions is given. The major categories of disease that produce focal lesions of the cardiac valves are presented.

Determinants of hospital survival following reoperative single valve replacement.

OBJECTIVE: To determine the indicators of risk for hospital death, patients undergoing reoperative valve replacement were analyzed METHODS: Four hundred and eighteen consecutive patients undergoing reoperative valve replacement from 1977 to 1994 were reviewed using univariate and multivariate analysis. RESULTS: Overall hospital mortality was 11.2% with 9.4% mortality with aortic valve replacement and 14.2% with mitral valve replacement (P=0.52). Mortality was 9.7% for patients less than 70 years of age compared with 19.4% for older patients (P=0.03), and was 8.5% for those with anoxia times less than 90 mins versus 21.9% for those with longer anoxia times (P=0.001). For first reoperations, 9.5% of patients died, while for patients undergoing second or more reoperation, mortality was 23.2% (P=0.01). While mortality increased from 8.9% to 19.0% with the addition of a concomitant procedure (P=0.008), it was not affected if the additional procedure was a coronary bypass (P=0. 96). The indication for surgery influenced outcome. Mortality was zero for thromboembolism, 9% for structural failure, 23% for nonstructural failure and 22% for endocarditis (P=0.006). For New York Heart Association (NYHA) functional class I patients, mortality was 1.6% compared with 22.3% for those in NYHA class IV (P=0.006). By multivariate analysis, however, only the indication for surgery and the NYHA functional class influenced survival. CONCLUSIONS: Reoperative valve surgery can be performed with a survival (88.8%) that is similar to the initial procedure (91.2%). The indication for surgery and NYHA functional class alone influenced outcome; therefore, possible early reoperation is indicated before clinical deterioration occurs.

Aortic medial changes associated with bicuspid aortic valve: myth or reality?

OBJECTIVE: To determine whether aortic medial changes are more severe in patients who require aortic valve replacement of congenitally bicuspid aortic valves (BAV) than in patients who require replacement of tricuspid aortic valves and acquired valvular disease (AVD). DESIGN: Aortas from autopsies of 14 patients with BAV and 25 with AVD were histologically assessed by two 'blinded' cardiovascular pathologists and analyzed independently with computer-aided morphometry. The aortic valves were examined for valvular fibrosis and calcification. SETTING: The patient population was from a tertiary-care facility. PATIENTS: Patients were selected by retrospective review of autopsy records for patient deaths after aortic valve replacement, over the period 1984 to 1995. RESULTS: There were no significant differences in age (P=0.89), sex (P=0.94), prevalence of systemic arterial hypertension (P=0.37), valvular degenerative changes (P=0.10 and P=1.0) or heart weights (P=0.60) between the two groups. Histological scores for aortic medial degenerative changes including elastic fragmentation, fibrosis and medionecrosis were not statistically different between the groups. However, morphometry demonstrated less elastic tissue in patients with BAV (P=0.003). CONCLUSION: Routine microscopy shows no significant difference in the degree of aortic medial degenerative changes between patients with BAV and AVD. However, morphometry shows less elastic tissue in the aortas of BAV patients. This may explain the anecdotal increase in aortic fragility and propensity for aortic dissection in these patients.

Aortitis with multiple aneurysms mimicking infective endocarditis.

Aortitis usually produces aortic insufficiency by aortic root dilation. In rare cases the inflammation may involve the aortic valve cusps, causing valvular insufficiency. A patient in whom aortitis produced valvular masses, with aortic and peripheral arterial aneurysms, embolic episodes and aortic insufficiency is described. Valve replacement for suspected infective endocarditis was complicated by homograft dehiscence and multiple false aneurysms. Although immunosuppression was successful in decreasing the patient's vasculitis, he became infected and died of complications of aspergillus infection.

Pathology of acute and chronic coronary stenting in humans.

BACKGROUND: Despite the increasing use of stents, few reports have described human coronary artery morphology early and late after stenting. METHODS AND RESULTS: Histology was performed on 55 stents in 35 coronary vessels (32 native arteries and 3 vein grafts) from 32 patients. The mean duration of stent placement was 39+/-82 days. Fibrin, platelets, and neutrophils were associated with stent struts 20 associated inflammatory cells compared with 44% of struts embedded in a lipid core and 36% of struts in contact with damaged media (P<0.001). Neointimal growth determined late histological success, and increased neointimal growth correlated with increased stent size relative to the proximal reference lumen area. Neointimal thickness was greater for struts associated with medial damage than struts in contact with plaque (P<0.0001) or intact media (P<0.0001). When matched for time since treatment, neointimal cell density in stented arteries was similar to that in unstented arteries that had undergone balloon angioplasty and showed similar proteoglycan deposition. CONCLUSIONS: Morphology after coronary stenting demonstrates early thrombus formation and acute inflammation followed by neointimal growth. Medial injury and lipid core penetration by struts result in increased inflammation. Neointima increases as the ratio of stent area to reference lumen area increases. Deployment strategies that reduce medial damage and avoid stent oversizing may lower the frequency of in-stent restenosis.

Successful surgical endarterectomy of a stented coronary artery.

An occlusion in this 61-year-old male's distal right coronary artery was initially successfully opened with balloon angioplasty and three "half" Palmaz-Schatz stents (Johnson and Johnson International Systems, Warren, NJ). Subsequent occlusion of the RCA occurred and prompted bypass grafting 2 years later. An extensive manual surgical endarterectomy removed the stents, demonstrating the technical feasibility of surgically removing failed stents in accessible coronary arteries.

Coronary artery erosion and dissection: an unusual complication of mitral annular calcification.

This article describes a 42-year-old male patient with a longstanding history of insulin-dependent diabetes mellitus, systemic arterial hypertension, and chronic renal failure. The patient had severe mitral annular calcification (MAC) identified at autopsy. This MAC was of an amorphous, caseous-appearing type; it displaced the posterior mitral valve leaflet and extruded into the myocardium of the lateral and posterolateral left ventricle to involve the epicardial surface. The MAC produced extramural erosion of the wall, and dissection into the media, of the first left/obtuse marginal coronary artery. This coronary artery involvement by, and other complications of, MAC are discussed.

Implantable cardioverter-defibrillators and the pathologist: comment and cautionary notes.

This paper briefly reviews the components of, the clinical uses of, the techniques to place, and the complications related to implantable cardioverter-defibrillators (ICDs). Information useful in the specific identification of ICDs is presented. A series of recommendations for the autopsy examination or postmortem explantation of ICDs by the pathologist is given. Because of the serious risk of injury to the pathologist possible with postmortem discharges of ICDs which have not been deactivated, and because of the risk of device explosion if the ICD is incinerated, a number of cautionary notes are provided. A brief case with occurrence of accidental postmortem discharge of an active ICD is also presented.

Evaluation of porcine valves prepared by dye-mediated photooxidation.

BACKGROUND: Previous studies demonstrated that dye-mediated photooxidation can stabilize bovine pericardium. Here, photooxidized porcine valve cusp and root tissue were assessed in comparison to fresh and glutaraldehyde-treated samples. METHODS AND RESULTS: In an in vitro tissue solubility test, both photooxidized and glutaraldehyde-treated tissues were resistant to protein extraction compared to fresh tissue. A rat subcutaneous model was used to test in vivo stability and calcification potential. In this study, four of the six fresh leaflets were not visible because of resorption while both photooxidized and glutaraldehyde-treated tissues were biostable. Mineral contents of the rat explants were much lower for both fresh and photooxidized leaflets when compared with glutaraldehyde-treated leaflets. Also, the aortic root calcified whether treated or not with the most mineral being associated with glutaraldehyde-treated root. Analysis of photooxidized porcine valves explanted from the mitral position in sheep indicated a material that was biostable and contained only minor calcification, perhaps due to deformed stents. CONCLUSIONS: Porcine valve tissue treated by dye-mediated photooxidation is biostable and resistant to calcification, and has potential for use in heart valve bioprostheses.

An unusual coronary vein lesion thrombus with calcification.

In this article, a patient with chronic renal failure and probable secondary hyperparathyroidism is described; calcification of a variety of cardiac and other structures complicated the latter. Calcification of an occlusive thrombus in the great cardiac vein and coronary sinus was identified by echocardiography, although not initially appreciated as such. The echocardiographic similarity of this lesion to mitral annular calcification is discussed.

Thyroid heterotopia as a rare cause of intrapericardial tumoral mass case report and review of the literature.

This article describes the interesting discovery of a large tumoral mass formed of heterotopic thyroid tissue inside the pericardial cavity of an elderly man who died of unrelated causes. Heterotopic thyroid tissue may be found in many locations throughout the body. Intracardiac and intrapericardial locations, however, are exceptionally rare-this is only the second report of intrapericardial thyroid heterotopia. Such cases may be explained by the proximity of the developing cardiac structures and the foregut, the latter containing thyroid primordia during early embryogenesis.

Hemophagocytic syndrome complicating cardiac transplantation.

Infection-associated hemophagocytic syndrome is one of the hemophagocytic disorders, and is most often seen in the pediatric population, typically in the setting of immunosuppression. We present the case of a 33-year-old man who had been well for more than 3 years following cardiac transplantation until he developed the infection-associated hemophagocytic syndrome. The patient had a fulminant downhill course, dying in shock 10 weeks after his first presentation. Serologic studies for Epstein-Barr virus suggested a remote infection; other viral and microbiologic studies were negative. The only previous report of infection-associated hemophagocytic syndrome complicating cardiac transplant appears to be that of a pediatric patient. The case presented illustrates the difficulties in antemortem diagnosis of this disorder, and in its treatment.

Arterial expression of the plasminogen activator system early after cardiac transplantation.

OBJECTIVES: Recent studies suggest that alterations in tissue thrombolysis as well as the inward migration of cells may be specific events that contribute to coronary artery narrowing after cardiac transplantation. Plasminogen activators and inhibitors play a central role in governing not only tissue thrombolysis, but also vascular cell migration. The purpose of this study was to examine arterial wall expression of the plasminogen activation system in coronary arteries during graft vascular disease initiation and progression. METHODS: Using in situ hybridization and immunocytochemistry, the expression patterns of uPA and PAI-1 in coronary arteries from cardiac allografts were compared to those of young individuals without disease. RESULTS: Both PAI-1 and uPA were over-expressed early after transplantation and as late as 27 months post grafting. Over-expression of these molecules preceded morphological evidence of graft vascular disease. Of special note was the adventitial expression of uPA and PAI-1 in microvessels and myofibroblasts. In contrast, the expression of uPA and PAI-1 in normal coronary arteries was confined to endothelial cells of the central lumen, as well as low levels of expression in intimal and medial smooth muscle cells. CONCLUSIONS: Despite morphologic similarities between normal and transplant coronary arteries, differences were noted in the vascular expression pattern of uPA and PAI-1. The exact role of these molecules in graft vascular disease requires further study; however, it is intriguing to consider that a local imbalance in the plasminogen system may contribute to arterial wall thrombosis and/or excessive cell migration and the genesis of complex vascular lesions.

Stenting of the left main coronary artery in the setting of acute myocardial infarction.

Coronary artery bypass grafting is the treatment of choice for significant left main coronary artery disease. A patient with an occluded left main coronary artery in the setting of myocardial infarction, who was given streptokinase and subsequently managed with intracoronary stenting, is reported.