Left ventricular outflow tract embolization and balloon assisted recapture of a SAPIEN XT prosthesis during transcatheter aortic valve replacement.

Transcatheter aortic valve replacement has emerged within the last decade as a proven alternative therapy in patients with severe aortic stenosis and prohibitive surgical risk. Despite rapidly evolving device technology and growing operator experience, peri-procedural complications are still relatively common. We present a case in which a SAPIEN XT prosthetic valve embolized into the left ventricular outflow tract. This was followed by balloon assisted recapture and subsequent successful implantation of the valve across the aortic annulus without significant hemodynamic compromise or surgical intervention. © 2015 Wiley Periodicals, Inc.

The effects of aging on the intimal region of the human saphenous vein: insights from multimodal microscopy and quantitative image analysis.

We hypothesized that structural remodeling associated with advancing age occurs in human saphenous veins. To address this hypothesis, we have identified structural remodeling in human saphenous veins by applying histochemistry, fluorescence staining and quantitative image analysis to specifically assess intimal area, intimal cellularity and intimal collagen content and organization. Saphenous veins were collected from patients undergoing coronary artery bypass graft surgery. Area measurements and cellularity were quantified using the image analysis software Stereo Investigator, employing planimetry and counting frames, respectively. Collagen content and organization were quantified in MetaMorph image analysis software based on measurements of color (hue, saturation, and intensity) from polarized light images. Intimal area and cellularity showed no statistically significant increases with age; in contrast, total collagen content showed a significant decrease with advancing age. Furthermore, collagen fiber types also demonstrated a statistically significant alteration with age; increases in age resulted in decreases in larger collagen fibers. No significant changes in small collagen fibers were identified. These results raise the possibility that age-associated structural alterations in total collagen content, specifically collagen fiber size, could be a factor in the etiology of age-associated venous diseases.

Atrial contractile protein content and function are preserved in patients with coronary artery disease and atrial fibrillation.

OBJECTIVES: Atrial fibrillation (AF) causes atrial contractile dysfunction. The focus of this study was to determine whether the contractile deficit of human AF is the result of altered contractile protein abundance and/or function. METHODS: Atrial tissue from patients with chronic AF undergoing open-heart surgery was compared with the tissue from patients in normal sinus rhythm (NSR). Myosin isoform composition and content were determined. Intact native thin filament and cardiac myosin contractile protein performance were independently assessed in an in-vitro motility assay. RESULTS: Myosin isoform expression and total myosin content were not different between AF and NSR. Calcium-activated native thin filament function was similar between AF and NSR as measured by calcium sensitivity and maximal activation. Myosin isolated from the atria of AF and NSR groups showed similar unloaded shortening speeds and isometric force generation. CONCLUSION: Unlike human ventricular dysfunction where contractile protein function is directly affected, the contractile deficit of AF is not the result of alterations in myosin content or contractile protein function.

Atypical presentation of anomalous origin of the left main coronary artery from the pulmonary artery.

Anomalous origin of the left main coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly that usually presents in childhood. Ninety percent of the patients with ALCAPA die within the first year of life without surgical intervention. In adults, ALCAPA is associated with left ventricular dysfunction, mitral regurgitation, and sudden death. The present report describes the case of an adult patient who presented with an abnormal stress test and ALCAPA was diagnosed during cardiac catheterization.

Cytokeratin-positive cells in the bone marrow of breast cancer patients and noncancer donors.

Detection of disseminated tumor cells in the bone marrow may provide important prognostic information in breast cancer patients. With few exceptions the number of stained cells scored as cancer is very low; there may be only 1 cell per slide. This makes definitive interpretation of cancer in marrow challenging. False-positive staining of marrow cells with cytokeratin (CK) antibody is relatively common and makes interpretation more difficult. In this report we focus on false-positive staining of marrow specimens from breast cancer patients and noncancer controls and demonstrate that the frequency of false-positive events is common. Bone marrow was collected from 23 cancer-free donors and 60 breast cancer patients. Samples were processed by Ficoll density gradient centrifugation and slides were prepared for immunocytochemical staining with CK and irrelevant (IR) antibody. Slides were evaluated manually and positive cells were categorized as tumor cells, hematopoetic cells, or questionable cells. False-positive staining events were commonly observed in noncancer cases stained with CK or IR antibodies and in breast cancer cases stained with IR antibody. There was little difference in the number of breast cancer marrow specimens scored as tumor cells regardless of whether the antibody used was CK or IR. It is important to devise improved criteria and methods for accurate detection and interpretation of disseminated tumor cells in the marrow of breast cancer patients.

Valves of the deep venous system: an overlooked risk factor.

Deep venous valves are frequent sites of deep venous thrombosis initiation. However, the possible contribution of the valvular sinus endothelium has received little attention in studies of thrombosis risk. We hypothesized that the endothelium of valve sinus differs from that of vein lumen with up-regulation of anticoagulant and down-regulation of procoagulant activities in response to the local environment. In pursuit of this hypothesis, we quantified endothelial protein C receptor (EPCR), thrombomodulin (TM), and von Willebrand factor (VWF) by immunofluorescence in great saphenous veins harvested at cardiac bypass surgery. We found significantly increased expression of EPCR and TM in the valvular sinus endothelium as opposed to the vein lumenal endothelium, and the opposite pattern with VWF (paired t test for TM and EPCR, each P < .001; for VWF, P = .01). These data support our hypothesis and suggest that variation in valvular sinus thromboresistance may be an important factor in venous thrombogenesis.

Matrix metalloproteinase and tissue inhibitor expression in atherosclerotic and nonatherosclerotic thoracic aortic aneurysms.

OBJECTIVES: The altered expression of matrix metalloproteinases and their inhibitors influences the formation of atherosclerotic abdominal aortic aneurysms. Their association with thoracic aneurysms is less clear. This study describes the expression of metalloproteinases and their inhibitors in atherosclerotic and nonatherosclerotic thoracic aneurysms, and compares these with age-matched controls. METHODS: Matrix metalloproteinase-2 and 9 activity were measured by antibody capture, and tissue inhibitor-1 and 2 levels were measured by enzyme-linked immunosorbent assay in 24 patients with atherosclerotic aneurysms and in 63 patients with nonatherosclerotic aneurysms. Gene expression was assessed with reverse transcriptase polymerase chain reaction. The results were compared with 17 controls. RESULTS: Data are in nanograms per milligram of protein. Matrix metalloproteinase-2 activity was greater in controls than in the atherosclerotic and nonatherosclerotic groups (80 +/- 67 vs 49 +/- 50 and 35 +/- 44, P = .002). Matrix metalloproteinase-9 activity was greater in the atherosclerotic group than in the nonatherosclerotic group and controls (11.7 +/- 15.7 vs 2.5 +/- 2.2 and 1.7 +/- 1.9, P = .001). Tissue inhibitor-1 and 2 levels were greater in controls than in either aneurysm group (tissue inhibitor of metalloproteinase-1: 376 +/- 192 vs 234 +/- 233 and 174 +/- 148, P = .003; tissue inhibitor of metalloproteinase-2: 143 +/- 74 vs 14 +/- 13 and 27 +/- 43, P < .001). Atherosclerotic aneurysms expressed more matrix metalloproteinase mRNA than controls. CONCLUSIONS: The metalloproteinase/tissue inhibitor phenotype of atherosclerotic thoracic aneurysms is similar to that of abdominal aneurysms. The diminished expression of metalloproteinases and tissue inhibitors in nonatherosclerotic thoracic aneurysms relative to aged controls may represent a loss of smooth muscle cells.

Acto-myosin crossbridge kinetics in humans with coronary artery disease: influence of sex and diabetes mellitus.

Risk of heart failure (HF) is influenced by sex and diabetes mellitus (DM). To better understand these interactions, sub-epicardial myocardium from 26 patients with coronary artery disease (CAD) undergoing coronary bypass surgery was examined in vitro using sinusoidal length perturbation analysis at varying [Ca(2+)] to determine the viscoelastic properties of myofilaments related to acto-myosin crossbridge kinetics. Half of the patients had CAD only (four female, F-CAD; nine male, M-CAD), while the other half had both CAD and Type 2 DM (six F-DM; seven M-DM). At maximal and sub-maximal myofilament Ca(2+) activation there was a significant effect of sex and disease on frequency of maximum oscillatory work output during sinusoidal perturbation (P<0.05). Myofilaments from F-CAD produced oscillatory work at significantly higher frequencies compared with M-CAD, while myofilaments from F-DM and M-DM produced work at similar frequencies. Correspondingly, minimum viscoelastic stiffness at maximum Ca(2+) activation occurred at significantly higher frequencies in F-CAD (5.0+/-0.3 Hz) than M-CAD (3.3+/-0.3 Hz), but at similar frequencies in F-DM (3.7+/-0.3 Hz) and M-DM (4.3+/-0.2 Hz). Thus, sex influences acto-myosin crossbridge kinetics in myofilaments isolated from CAD patients. These sex-related differences were absent in DM, suggesting that differences in the properties of cardiac muscle contribute to reported sex differences in the incidence and mortality of HF in DM.

The detection of isolated tumor cells in bone marrow comparing bright-field immunocytochemistry and multicolor immunofluorescence.

BACKGROUND: The detection of isolated tumor cells in bone marrow by immunocytochemistry (ICC) has been reported to predict progression of early-stage breast cancer. The most common staining procedure uses bright-field ICC with cytokeratin (CK) antibodies to label isolated tumor cells. However, this method can result in false-positive staining events. We used multicolor immunofluorescence (IF) to develop a more specific assay for detecting isolated tumor cells in marrow samples from breast cancer patients. METHODS: We compared ICC and IF side by side for detection of cancer cells and false-positive staining events on bone marrow aspirates from breast cancer patients, bone marrow from healthy donors, and healthy donor blood spiked with cancer cells. The primary target for isolated tumor cell detection was CK for both methods. IF used an additional set of antibodies to label hematopoietic cells (HCs). RESULTS: The detection rate of CK+ events in breast cancer patient bone marrow aspirates was 18 (58%) of 31 for ICC and 21 (68%) of 31 for IF. However, with IF, 17 of 21 CK+ cases were stained with HC markers and thus were identified as false-positive events. A surprisingly high CK+ event rate was observed in healthy donor blood and marrow. In all healthy donor samples, CK+ events were readily identified as HCs by IF. Detection sensitivity of spiked cancer cells in donor blood was similar for both methods. CONCLUSIONS: There is a high frequency of CK+ events in blood and marrow, and it is important to note that this is observed both in patients with and those without cancer. IF with multiple HC markers allows straightforward discrimination between CK+ cells of hematopoietic and nonhematopoietic origin.

Regional differences in the force-frequency relation of human left ventricular myocardium in mitral regurgitation: implications for ventricular shape.

Sphericalization of the left ventricular (LV) chamber shape in patients with mitral regurgitation (MR) contributes to increased LV wall stress and energy consumption. On the basis of previous observations, we hypothesized the existence of regional differences in the force-frequency relation (FFR) within the LV that may contribute to its shape. Accordingly, in the present study, we assessed regional variation in the FFR in patients undergoing surgery for chronic, nonischemic MR with class II-III heart failure symptoms and related our findings to the in vivo LV shape. FFRs (steady-state isometric twitches, 0.2-3.4 Hz, 37 degrees C) were evaluated in MR myocardium from the LV subepicardial free wall (MR-FW) and papillary muscle (MR-PM) and from the subepicardial free wall in coronary artery bypass graft patients with normal LV contraction patterns [nonfailing (NF)]. Ascending slope, optimal stimulation frequency, and maximal twitch tension of the FFR were depressed in MR-FW and MR-PM compared with NF (P < 0.05). FFR depression was greater in MR-PM than in MR-FW. Between 107 and 134 beats/min, twitch tension became weaker in MR-PM, whereas it increased in MR-FW. Elevation of intracellular cAMP with forskolin eliminated FFR depression in MR-FW but not in MR-PM. MR-PM also had a 35% lower myosin heavy chain content and slowed twitch kinetics. In MR patients, the echocardiographic end-diastolic LV shape (end-diastolic eccentricity index = long axis/short axis) correlated with the ratio of ascending FFR slopes such that the end-diastolic eccentricity index increased 10% per 15% increase in slope ratio (r = 0.88, P = 0.01). These regional differences in the frequency dependence of contractility between the free wall and papillary myocardium may contribute to changes in LV shape in MR as well as during exercise.

Thin-filament-based modulation of contractile performance in human heart failure.

BACKGROUND: The contribution of the sarcomere's thin filament to the contractile dysfunction of human cardiomyopathy is not well understood. METHODS AND RESULTS: We have developed techniques to isolate and functionally characterize intact (native) thin filaments obtained from failing and nonfailing human ventricular tissue. By use of in vitro motility and force assays, native thin filaments from failing ventricular tissue exhibited a 19% increase in maximal velocity but a 27% decrease in maximal contractile force compared with nonfailing myocardium. Native thin filaments isolated from human myocardium after left ventricular assist device support demonstrated a 37% increase in contractile force. Dephosphorylation of failing native thin filaments resulted in a near-normalization of thin-filament function, implying a phosphorylation-mediated mechanism. Tissue expression of the protein kinase C isoforms alpha, beta1, and beta2 was increased in failing human myocardium and reduced after left ventricular assist device support. CONCLUSIONS: These novel findings demonstrate that (1) the thin filament is a key modulator of contractile performance in the failing human heart, (2) thin-filament function is restored to near normal levels after LVAD support, and (3) the alteration of thin-filament function in failing human myocardium is mediated through phosphorylation, most likely through activation of protein kinase C.

Matrix metalloproteinase activity in thoracic aortic aneurysms associated with bicuspid and tricuspid aortic valves.

OBJECTIVE: Matrix metalloproteinases are endopeptidases that function in cell matrix turnover. Abnormal matrix metalloproteinase activity has been implicated in the formation of atherosclerotic abdominal aortic aneurysms. Recent studies suggest that abnormal matrix metalloproteinase activity may also be associated with the formation of atherosclerotic and nonatherosclerotic thoracic aortic aneurysms. Bicuspid aortic valves are associated with an intrinsic aortic pathology that predisposes to formation of proximal thoracic aneurysms while tricuspid aortic valves are not. The objective of this study was to compare the activities of matrix metalloproteinases and levels of their inhibitors in thoracic aneurysms of patients with bicuspid and tricuspid aortic valves. METHODS: Endogenous and total activity of matrix metalloproteinase-2 and matrix metalloproteinase-9 were measured in proximal nonatherosclerotic thoracic aortic aneurysms of 16 patients with bicuspid aortic valves and 12 patients with tricuspid aortic valves. Levels of tissue inhibitor metalloproteinase-1 and -2 were also measured. Results were standardized to total protein (mg). RESULTS: Total matrix metalloproteinase-2 activity was greater in aneurysms associated with bicuspid valves when compared with those from tricuspid valves (43 +/- 11 ng/mg vs 14 +/- 2 ng/mg, P =.02). Total matrix metalloproteinase-9 activity was also greater in aneurysms associated with bicuspid aortic valves (4.0 +/- 0.9 vs 1.5 +/- 0.3, P =.02). There was no meaningful difference between groups in levels of tissue inhibitor-1 and -2. CONCLUSION: The increased activity of matrix metalloproteinases in the walls of aneurysms associated with bicuspid aortic valves may partly explain the predilection to aneurysm formation in these patients.

Myosin from failing and non-failing human ventricles exhibit similar contractile properties.

In non-failing human myocardium, V1 myosin comprises a small amount (<10%) of the total myosin content, whereas end-stage failing hearts contain nearly 100% V3 myosin. It has been suggested that this shift in V1 myosin isoform content may contribute to the contractile deficit in human myocardial failure. To test this hypothesis, myosin was isolated from human failing and non-failing ventricles, and non-failing atria. Performance was assessed in in vitro motility and isometric force assays. Consistent with prior reports, a small amount of V1 myosin was present in both non-failing (6.2 +/- 1.0%) and failing (3.5 +/- 1.4%) ventricular tissues. No difference in isometric force or unloaded shortening velocity was observed for failing and non-failing ventricular myosin irrespective of myosin isoform content. Atrial tissue expressing predominantly V1 myosin (66.7 +/- 4.1%) generated half the force but greater velocity compared with ventricular tissue, expressing predominantly V3 myosin. In additional experiments, rabbit cardiac myosin was used in a calcium regulated assay system to determine if V1 and V3 isoforms differentially affect thin filament activation. Half-maximal calcium activation was similar for the two cardiac isoforms. A 1:9 mixture of V1/V3 myosin, simulating isoform composition in non-failing human myocardium, was indistinguishable from 100% V3 myosin (simulating the failing state) with regard to velocity of shortening and average force. These data suggest that the myosin isoform shift reported in human myocardial failure does not significantly contribute to the contractile deficit of this disease.