Ivan P. Casserly

Convergence of atherosclerosis and Alzheimer's disease: inflammation, cholesterol, and misfolded proteins

Late-onset sporadic Alzheimers disease is a heterogeneous disorder. In elderly patients, increasing evidence suggests a link between this neurodegenerative disease, and vascular risk factors and atherosclerosis. The nature of this link remains speculative. Some investigators have suggested that the disease arises as a secondary event related to atherosclerosis of extracranial or intracranial vessels. A toxic effect of vascular factors on the microvasculature of susceptible brain regions has also been argued. An alternative explanation is that atherosclerosis and Alzheimers disease are independent but convergent disease processes. This hypothesis is lent support by observations of shared epidemiology, pathophysiological elements, and response to treatment in both disorders. It provides a potential framework for an improved understanding of the pathogenesis of Alzheimers disease, especially in elderly patients with vascular risk factors, and offers some promise toward the search for preventive and therapeutic treatments.

Propensity Analysis of Long-Term Survival After Surgical or Percutaneous Revascularization in Patients With Multivessel Coronary Artery Disease and High-Risk Features

Background—Although most randomized clinical trials have suggested that long-term survival rates after percutaneous coronary intervention (PCI) or surgical multivessel coronary revascularization (CABG) are equivalent, some post hoc analyses in high-risk groups and adjustment for severity of coronary disease have suggested higher mortality after PCI. Methods and Results—We studied 6033 consecutive patients who underwent revascularization in the late 1990s. PCI was performed in 872 patients; 5161 underwent CABG. Half the patients had significant left ventricular dysfunction or diabetes. Propensity analysis to predict the probability of undergoing PCI according to 22 variables and their interactions was used. The C-statistic for this model was 0.90, indicating excellent discrimination between treatments. There were 931 deaths during 5 years of follow-up. The 1- and 5-year unadjusted mortality rates were 5% and 16% for PCI and 4% and 14% for CABG (unadjusted hazard ratio, 1.13; 95% CI, 1.0 to 1.4; P =0.07). PCI was associated with an increased risk of death (propensity-adjusted hazard ratio, 2.3; 95% CI, 1.9 to 2.9; P <0.0001). This difference was observed across all categories of propensity for PCI and in patients with diabetes or left ventricular dysfunction. Other independent predictors of mortality (P ≤0.01 for all) were renal dysfunction, age, diabetes mellitus, chronic lung disease, peripheral vascular disease, left main trunk stenosis, and extent of coronary disease (Duke angiographic score). Conclusions—In patients with multivessel coronary artery disease and many high-risk characteristics, CABG was associated with better survival than PCI after adjustment for risk profile.

Percutaneous Transcatheter Closure of Prosthetic Mitral Paravalvular Leaks : Are We There Yet?

A potential complication of mitral valve replacement surgery is the development of a paravalvular leak (PVL). Percutaneous transcatheter closures of PVLs using a wide array of devices have been reported in the literature, although the procedural success rate of this approach remains variable. One major challenge of transcatheter mitral PVL closure lies in the ability to adequately visualize the area of interest to facilitate defect crossing and equipment selection. Furthermore, the current spectrum of devices available for off-label use in the closure of these unique defects remains limited. This review examines the current state of transcatheter prosthetic mitral PVL closure, describes our institutions experience using advanced imaging modalities for procedural guidance, and illustrates some of the limitations associated with using existing devices in transcatheter PVL closure.

Quantitative assessment of the conformational change in the femoropopliteal artery with leg movement

The unique physical forces exerted on the femoropopliteal (FP) artery during movement have been implicated in the high rates of restenosis and stent fracture in this artery. Conformational changes in the FP artery during movement are important surrogates of these forces. This study sought to quantify the conformational change in the FP artery between the straight‐leg (SL) and crossed‐leg (CL) positions.

Assessment of functional status and quality of life in claudication.

BACKGROUND Treadmill walking is commonly used to evaluate walking impairment and efficacy of treatment for intermittent claudication (IC) in clinical and research settings. Although this is an important measure, it does not provide information about how patients perceive the effects of their treatments on more global measures of health-related quality of life (HRQOL). METHODS PubMed/Medline was searched to find publications about the most commonly used questionnaires to assess functional status and/or general and disease-specific HRQOL in patients with peripheral artery disease (PAD) who experience IC. Inclusion criteria for questionnaires were based on existence of a body of literature in symptomatic PAD. RESULTS Six general questionnaires and seven disease-specific questionnaires are included, with details about the number of domains covered and how each tool is scored. The Medical Outcomes Study Short Form 36-item questionnaire and Walking Impairment Questionnaire are currently the most used general and disease-specific questionnaires at baseline and after treatment for IC, respectively. CONCLUSIONS The use of tools that assess functional status and HRQOL has importance in both the clinical and research areas to assess treatment efficacy from the patients perspective. Therefore, assessing HRQOL in addition to treadmill-measured walking ability provides insight as to the effects of treatments on patient outcomes and may help guide therapy.

Retrograde approach to recanalization of complex tibial disease

A significant proportion (∼20%) of patients with complex tibial artery occlusions cannot be treated using a conventional antegrade approach. We report our experience using the retrograde approach for the treatment of complex tibial artery occlusive disease using retrograde pedal/tibial access in 13 limbs from 12 patients. Retrograde pedal/tibial access was achieved in all cases (facilitated by surgical cutdown in one case), and procedural success was achieved in 11 of 13 limbs (85%). Based on this experience, a discussion of clinical and technical aspects of the retrograde pedal/tibial approach is provided, and a new classification for tibial artery occlusive disease is proposed.

Patterns of artery disease in 450 patients undergoing revascularization for critical limb ischemia: Implications for clinical trial design

OBJECTIVE The pattern and distribution of arterial occlusions and stenoses in patients with critical limb ischemia presenting at two academic medical centers was described. METHODS From January 1998 to December 2006, 450 consecutive critical limb ischemia patients who underwent arteriography and infrainguinal revascularization at the University of Colorado Health Sciences Center or Southern Illinois University were retrospectively evaluated. Demographics, clinical morbidities, and Fontaine stage were recorded. The arterial tree was categorized into three groups: the aorta and iliac arteries (A-I); the common femoral, superficial femoral, and profunda femoral arteries (Fem); and the popliteal and tibial arteries (Pop-Tib). Arterial segments within groups were categorized as subcritical stenoses (patent or <50% stenoses), critical stenoses (single or multiple >50% stenoses), or occluded (segmental occlusions of any length). Patients with diabetes mellitus, end-stage renal disease, and Fontaine stage (III vs IV) were analyzed for differing disease patterns according to their chart history. RESULTS Occlusive disease was present in 5% in all arterial segments (A-I + Fem + Pop-Tib), in 1% in the A-I + Fem group, in 2% in the A-I + Pop-Tib group, in 3% in A-I group, in 4% in the Fem group, in 30% in the Fem + Pop-Tib group, and in 55% in the Pop-Tib group. Descriptive comparisons among subgroups demonstrated a 61% to 69% prevalence of popliteal and tibial occlusive patterns in patients with diabetes mellitus, end-stage renal disease, and Fontaine stage IV. Furthermore, 65% of patients with Pop-Tib occlusions had associated critical stenoses in the proximal arterial groups. CONCLUSION More than half of critical limb ischemia patients undergoing infrainguinal revascularization have arterial occlusions in the popliteal or tibial arterial segments, or both, with associated critical stenoses in the femoral arterial segments, which is even greater in the subgroups with diabetes mellitus, end-stage renal disease, and Fontaine stage IV. Knowledge of such occlusive patterns is important for the development of novel infrainguinal endovascular and angiogenesis therapies for critical limb ischemia.

Transcatheter closure of recurrent postmyocardial infarction ventricular septal defects utilizing the Amplatzer postinfarction VSD device: a case series.

The initial therapy for postmyocardial infarction ventricular septal defects is surgical repair of the defect. Unfortunately, a significant number of patients develop recurrent ventricular septal defects (VSDs) following operative repair. Transcatheter closure offers an alternative to reoperation in these critically ill patients. We present a series of four patients in whom recurrent ventricular septal defects were closed using an Amplatzer VSD device. Cathet Cardiovasc Intervent 2003;59:238–243.

Glycoprotein IIb/IIIa antagonists - from bench to practice

Abstract. The central role played by the αIIbβ3 receptor in platelet aggregation, and hence in platelet thrombosis, has led to the development of a number of parenteral and oral glycoprotein (GP) IIb/IIIa inhibitors for use in cardiovascular disease states, such as acute coronary syndromes and stroke. The predominant effect of these agents is to inhibit platelet aggregation, although studies of αIIbβ3 receptor function and various GP IIb/IIIa inhibitors have demonstrated the potential for these agents to produce effects on other aspects of platelet function, in addition to non-platelet effects. Overall, clinical studies have demonstrated an impressive beneficial effect for parenteral agents in reducing ischemic complications following percutaneous intervention, and a more modest beneficial effect in the treatment of patients with acute coronary syndromes. Trials with oral GP IIb/IIIa inhibitors in similar patient populations have demonstrated toxicity, manifested by an increased mortality in treated patients. Increased understanding of molecular aspects of both αIIbβ3 receptor function and the effects of GP IIb/IIIa inhibition may help explain some of the inconsistency in recently reported clinical studies with parenteral agents, and the frank toxicity of oral agents. Such studies may also hold the key to the development of newer agents with enhanced therapeutic benefit.

Initial clinical experience of selective coronary angiography using one prolonged injection and a 180° rotational trajectory

Evaluate the safety of prolonged coronary injections during a rotational acquisition covering 180°.