Cardiovascular Revascularization Medicine

Google medicine

Ron Waksman — 2012-01-01

There is no doubt that one of the most profound transformations in medicine is happening right now. It's not a drug or a stent or a new therapy—it's Google. Fifteen years ago, Google set out on a mission “to organize the world's information and make it universally accessible and useful” and, in doing so, transformed the global information landscape. In recent years, Google has digitized the vast majority of the world's libraries, and the majority of published medical content is within reach in seconds.

The evaluation of creatinine clearance, estimated glomerular filtration rate and serum creatinine in predicting contrast-induced acute kidney injury among patients undergoing percutaneous coronary intervention

2011-11-17

Abstract: Purpose: The purpose of the study was to compare creatinine clearance (CrCl), estimated glomerular filtration rate (eGFR) and serum creatinine (SCr) in predicting contrast-induced acute kidney injury (CI-AKI), dialysis and death following percutaneous coronary intervention (PCI).Methods and Materials: Data were prospectively collected on 7759 consecutive patients within the Dartmouth Dynamic Registry undergoing PCI between January 1, 2000, and December 31, 2006. Renal function was measured at baseline and within 48 h after PCI using three methods: CrCl using the Cockcroft–Gault equation, eGFR using the abbreviated Modification of Diet in Renal Disease equation and SCr. We compared CrCl, eGFR and SCr in predicting CI-AKI, post-PCI dialysis-dependent renal failure and in-hospital mortality. Areas under the receiver operating characteristic curve (ROC) were calculated using logistic regression and tested for equality.Results: On univariable analysis, CrCl [ROC: 0.69; 95% confidence interval (CI): 0.67–0.72] predicted CI-AKI better than eGFR (ROC: 0.67; 95% CI: 0.64–0.70) (P=.013) and SCr (ROC: 0.64; 95% CI: 0.61–0.67) (P<.001). Creatinine clearance (ROC: 0.73; 95% CI: 0.69–0.77) and eGFR (ROC: 0.70; 95% CI: 0.65–0.74) outperformed SCr for predicting in-hospital mortality. On multivariable analysis, CrCl (ROC: 0.77; 95% CI: 0.75–0.80), SCr (ROC: 0.78; 95% CI: 0.76–0.80) and eGFR (ROC: 0.77; 95% CI: 0.75–0.80) predicted CI-AKI well. Creatinine clearance (ROC: 0.88; 95% CI: 0.85–0.90) and eGFR (ROC: 0.87; 95% CI: 0.85–0.90) were strong independent predictors of in-hospital mortality.Conclusions: Creatinine clearance, eGFR and SCr predict CI-AKI equally well. Creatinine clearance and eGFR are strong independent predictors of in-hospital mortality.

The role of oxidized phospholipids, lipoprotein (a) and biomarkers of oxidized lipoproteins in chronically occluded coronary arteries in sudden cardiac death and following successful percutaneous revascularization

2011-11-14

Abstract: Aims: OxPL are pro-inflammatory and may mediate atherogenesis, thrombosis and endothelial dysfunction. We studied the histological presence and temporal increases in oxidized phospholipids on apolipoprotein B-100 particles (OxPL/apoB), lipoprotein (a) [Lp(a)] and biomarkers of oxidized lipoproteins in subjects with chronic total coronary occlusions (CTO) with sudden cardiac death (SCD) and following percutaneous coronary intervention (PCI).Methods: Eight subjects with SCD and CTO and 33 patients with successful PCI of CTO were included. Blood samples were drawn before PCI, immediately post-PCI, at 6 and 24 h, at 3 days and at 1 week. Plasma levels of OxPL/apoB, Lp(a), IgG and IgM autoantibodies to malondialdehyde (MDA) low-density lipoprotein and apoB-immune complexes were measured in all samples and compared with previous data from 141 patients undergoing PCI of non-CTO vessels.Results: Immunohistochemistry of coronary CTOs revealed OxPL and MDA-like epitopes, particularly in areas of recanalized and organized thrombus and neovascularization. Following PCI, OxPL/apoB and Lp(a) levels, expressed as percent change from baseline levels before PCI, rose gradually and progressively over the next 7 days. In contrast, levels of OxPL/apoB and Lp(a) in non-CTO vessels rose immediately post PCI and then dropped rapidly to baseline within 24 h.Conclusions: CTOs contain immunohistological evidence of OxPL and MDA-like epitopes. Successful PCI of CTOs results in a slower increase in OxPL/apoB and Lp(a) but higher increase in IgM immune complexes compared to non-CTO vessels. Pro-inflammatory oxidation-specific epitopes may impact development of CTOs and affect outcomes following PCI that can be evaluated in larger clinical trials.

Antegrade approach for percutaneous interventions of ostial superficial femoral artery: outcomes from a prospective series of diabetic patients presenting with critical limb ischemia

2011-11-24

Abstract: Objectives: This is a prospective evaluation of percutaneous interventions (PTAs) performed by the antegrade femoral approach in diabetic patients with critical limb ischemia (CLI) and ostial superficial femoral artery (SFA) lesions.Methods: The puncture site was selected according to duplex scan analysis and physical examination (brachial, crossover, or antegrade). In cases of antegrade approach, a bare needle angiogram of the femoral bifurcation was performed in order to have an adequate distance (>2 cm) from the target lesion.Results: Between January 2010 and August 2011, 64 diabetic patients underwent PTA for ostial SFA lesions.Crossover or brachial approach was electively adopted in 19/64 (30%) patients. The antegrade bare needle angiogram was performed in the remaining 45/64 (70%) patients. In two patients, the vascular anatomy was considered not suitable for antegrade approach, and they were treated in crossover. Technical success was achieved in 38/45 (84%) of patients. During hospital stay, one patient had SFA stent thrombosis treated with urgent bypass grafting.Conclusions: The antegrade approach can be safely performed in most patients presenting with CLI and ostial SFA lesions. The use of clinical and radiographic criteria correctly identifies patients with ostial SFA lesions suitable for an antegrade approach in 42/44 (95%) of cases.

Blood flow to the heart from noncoronary arteries: an intriguing but challenging research field

2011-10-20

Abstract: Introduction: It has been proven that blood supply to the heart can include blood from noncoronary collateral circulation. Whether this network can somehow be augmented to provide an alternative therapy for ischemic patients is an intriguing hypothesis with no clear answer yet due to the challenging nature of this research field. In an attempt to enhance noncoronary collateral blood flow, we experimented with left internal thoracic artery ligature and angiogenic growth factors in a canine model.Materials and methods: Eight dogs weighing between 20 and 29 kg were scheduled for three operations each. Neutron-activated microspheres were used for blood flow measurement throughout the study. The first operation was a left thoracotomy for ameroid constrictor positioning at the proximal segment of the circumflex coronary artery. Three weeks later the left internal thoracic artery was ligatured distally. A micro-pump was positioned in the mediastinum, connected with a small catheter inserted in the proximal segment of the left internal thoracic artery for slow delivery of vascular endothelial growth factor. The protocol called for a coronary angiography 4 weeks later, sacrifice of the animals, and explantation of the heart for microsphere analysis.Results: Four of the dogs failed to tolerate ameroid constrictor positioning by thoracotomy and died after the first operation. The remaining four dogs underwent a second operation to ligate their left internal thoracic arteries and implant micro-pumps with catheters. The implant was a success, but only one dog survived in the postoperative period. When the last dog was voluntarily sacrificed after a third operation, coronary angiography showed no neovascularization, nor did heart slice analysis reveal microspheres.Conclusions: Despite the technical challenge of building research protocols to exactly quantify blood from noncoronary arteries, there are many historical, anatomical, physiopathological, clinical, radiological, and surgical indications suggesting that blood flow from extracardiac structures may play an important role in ischemic heart disease. Our preliminary investigation combining internal thoracic artery occlusion and angiogenic growth factors was unsuccessful for several reasons, the main one being it was too heavy a protocol for the dogs. Despite this, we think that noncoronary collateral blood flow represents an intriguing research field worthy of debate and further study.

Bridging therapy after recent stent implantation: case report and review of data

Jeffrey D. Wessler, Fidencio Saldana, Robert P. Giugliano — 2011-10-24

Abstract: For patients requiring surgery within their first year following coronary stent placement, maximizing the prevention of stent thrombosis with antiplatelet therapy while minimizing the risk of intraoperative bleeding has become a management challenge for cardiologists, surgeons and anesthesiologists. In this manuscript, we describe a case of a patient who received three stents (two of which were drug-eluting) and 7 months later was bridged with intravenous eptifibatide, a short-acting glycoprotein (GP) IIb/IIIa inhibitor, for 3 days prior to bronchoscopy and cervical mediastinoscopy for a suspected lung cancer. We then review the current literature for data and guidelines describing the use of short-acting GP IIb/IIIa as bridge therapy. Finally, we provide recommendations, based on our experience combined with this review, for bridge therapy in the perioperative period for patients with recent coronary stents.

Complications of transradial catheterization

Vineet K. Dandekar, Mladen I. Vidovich, Adhir R. Shroff — 2011-11-24

Abstract: Cardiac catheterization via the transradial approach has increased in the United States over the past few years; however, wide-scale adoption still lags in comparison to many international health care systems. Transradial catheterization has a unique set of complications and risks that each operator must appreciate. Radial artery spasm and radial artery occlusion are the most common complications, while bleeding complications such as hematomas and perforations are much less frequent. Each of these issues can be managed successfully with minor changes to one's practice. In this review of the current state of the art, the reader will develop an appreciation for the prevalence of each of the common complications as well as the less common, but potentially highly morbid, events. Throughout this evidence-based review, practical prevention strategies and specific treatment pathways are described for each issue that is covered.

Bifurcation stenting: the current state of play

Michael Mahmoudi, Ron Waksman — 2011-01-27

Coronary bifurcation lesions are encountered in approximately 15% of percutaneous coronary interventions (PCIs) . Early experience using balloon angioplasty was discouraging due to complications such as acute closure and restenosis in both the main branch (MB) and the side branch (SB) . Although the introduction of bare-metal stents (BMS) in the treatment of bifurcation lesions provided some improvements over balloon angioplasty, results continued to be disappointing, with a 38% rate of target lesion revascularization (TLR) at 6 months and a 32% rate of major adverse cardiac events (MACEs) at 1 year . The beneficial effects of drug-eluting stents (DESs) in reducing restenosis in both simple and complex coronary lesions appear to extend to bifurcation lesions regardless of whether a single- or multiple-stent strategy is employed . However, despite the advances in both stent technology and technique, the treatment of bifurcation lesions continues to pose a challenge to the interventional cardiologist due to a combination of technical complexity and associated morbidity. This review provides a brief summary of the techniques used in the treatment of such lesions and to summarize both the randomized and clinical registry data in the treatment of coronary bifurcation lesions.

Use of the CrossBoss catheter for crossing superficial femoral artery chronic total occlusions

Michael Luna, Subhash Banerjee, Emmanouil S. Brilakis — 2011-07-08

Abstract: The CrossBoss chronic total occlusion catheter has been developed for the treatment of coronary chronic total occlusions. We report a novel use of the CrossBoss catheter for the crossing of a superficial femoral artery chronic total occlusion in three patients after conventional guidewire techniques failed.

Acute myocardial infarction and cardiac arrest due to coronary artery perforation after mitral valve surgery: successful treatment with a covered stent

Harshal Sheth, Rajiv S. Swamy, Atman P. Shah — 2011-08-19

Abstract: We present a case of a gentleman who presented with acute myocardial infarction and cardiac arrest 6 days after undergoing mitral valve replacement surgery. Immediate coronary angiography revealed perforation of the left circumflex artery which was successfully treated with a covered stent. This report details the successful percutaneous treatment of an exceedingly rare complication of mitral valve surgery.

Takotsubo cardiomyopathy: reversible elevation in microcirculatory resistance

2011-08-19

Abstract: We present a case of takotsubo cardiomyopathy and demonstrate an initial elevation of microcirculatory resistance (IMR) that reduced on follow-up evaluation. This corresponded with improvements in left ventricular function. We postulate that the changes in microvascular resistance reflect favourable left ventricular microvascular remodelling. The measurement of IMR, a novel marker of microcirculatory dysfunction, provides novel insights into the pathophysiology of this condition.

Percutaneous blade and balloon atrioseptostomy as a supplement to extracorporeal membrane oxygenation as a bridge to heart transplantation

Ziad Dahdouh, Vincent Roule, Thérèse Lognoné, Rémi Sabatier, Gilles Grollier — 2011-07-08

Abstract: In patients with severe ventricular dysfunction, the extracorporeal membrane oxygenation (ECMO) could be insufficient to discharge the left ventricle. The percutaneous blade and balloon atrioseptostomy that requires transeptal catheter-based experience could be an advisable technique to supplement assistance as a bridge to partial recovery or to heart transplantation. We present a case of a young male who presented for cardiogenic shock with a huge thrombus in the left main coronary artery in whom blade and balloon atrioseptostomy in addition to the ECMO was helpful to bail out and to perform heart transplantation.

Alcohol septal ablation in hypertrophic obstructive cardiomyopathy

2011-02-08

An 80-year-old female with a history of coronary artery disease and post cardiac bypass surgery was admitted with increasing shortness of breath and fatigue. Electrocardiogram showed left ventricular hypertrophy with marked nonspecific ST-T changes. Transthoracic echocardiography demonstrated normal systolic function with asymmetric septal hypertrophy (25 mm) and increased left ventricular outflow velocity indicating a gradient up to 144 mmHg (). Coronary angiography demonstrated patent grafts. Hemodynamics demonstrated the classic Brockenbrough–Braunwald phenomenon: a resting gradient of 62 mmHg in left ventricular outflow tract increased the post ventricular premature beat to 160 mmHg; diminution in arterial pressure; and the appearance of a developing spike-and-dome pulse-wave configuration ().