Ovid Technologies (Wolters Kluwer Health)

We studied the effects of afterload reduction in chronic severe aortic insufficiency by measuring the hemodynamic response to oral hydralazine in 10 consecutive patients. Hemodynamics were also measured during maximal exercise in eight of these patients. At rest, hydralazine reduced pulmonary artery wedge pressure from 14 to 9 mm Hg (p less than 0.01), and increased cardiac index by 70% and stroke volume index by 35% (both p less than 0.001). Before hydralazine, pulmonary artery wedge pressure exceeded 20 mm Hg in five patients during maximal exercise; with hydralazine, at identical levels of exercise, pulmonary artery wedge pressure remained below 20 mm Hg in all patients. For the group, hydralazine reduced pulmonary artery wedge pressure from 21 to 12 mm Hg (p less than 0.05) and increased cardiac index by 31% (p less than 0.05) during exercise; changes in stroke volume index were more variable and there was no significant increase for the group, although several patients increased stroke volume substantially and the overall increase was 34%. These data show that afterload reduction has beneficial effects on cardiac performance in chronic severe aortic insufficiency both at rest and during exercise. Hydralazine may be of use in such patients either in preparation for valve replacement or as interim therapy.

Background— Recent studies demonstrated that in vivo and ex vivo MRI can characterize the components of the carotid atherosclerotic plaque, such as fibrous tissue, lipid/necrotic core, calcium, hemorrhage, and thrombus. The purpose of this study was to determine whether in vivo high-resolution multicontrast MRI could accurately classify human carotid atherosclerotic plaque according to the American Heart Association classification.

Methods and Results— Sixty consecutive patients (mean age 70 years; 54 males) scheduled for carotid endarterectomy were imaged with a 1.5-T scanner after informed consent was obtained. A standardized protocol was used to obtain 4 different contrast-weighted images (time of flight and T1-, PD-, and T2-weighted) of the carotid arteries. Best voxel size was 0.25×0.25×1 mm ³ . Carotid plaques were removed intact and processed for histological examination. Both MR images and histological sections were independently reviewed, categorized, and compared. Overall, the classification obtained by MRI and the American Heart Association classifications showed good agreement, with Cohen’s κ (95% CI) of 0.74 (0.67 to 0.82) and weighted κ of 0.79. The sensitivity and specificity, respectively, of MRI classification were as follows: type I-II lesions, 67% and 100%; type III lesions, 81% and 98%; type IV-V lesions, 84% and 90%; type VI lesions, 82% and 91%; type VII lesions, 80% and 94%; and type VIII lesions, 56% and 100%.

Conclusions— In vivo high-resolution multicontrast MRI is capable of classifying intermediate to advanced atherosclerotic lesions in the human carotid artery and is also capable of distinguishing advanced lesions from early and intermediate atherosclerotic plaque.

Background —The corrected TIMI frame count (CTFC) is the number of cine frames required for dye to first reach standardized distal coronary landmarks, and it is an objective and quantitative index of coronary blood flow.

Methods and Results —The CTFC was measured in 1248 patients in the TIMI 4, 10A, and 10B trials, and its relationship to clinical outcomes was examined. Patients who died in the hospital had a higher CTFC (ie, slower flow) than survivors (69.6±35.4 [n=53] versus 49.5±32.3 [n=1195]; P =0.0003). Likewise, patients who died by 30 to 42 days had higher CTFCs than survivors (66.2±36.4 [n=57] versus 49.9±32.1 [n=1059]; P =0.006). In a multivariate model that excluded TIMI flow grades, the 90-minute CTFC was an independent predictor of in-hospital mortality (OR=1.21 per 10-frame rise [95% CI, 1.1 to 1.3], an ≈0.7% increase in absolute mortality for every 10-frame rise; P <0.001) even when other significant correlates of mortality (age, heart rate, anterior myocardial infarction, and female sex) were adjusted for in the model. The CTFC identified a subgroup of patients with TIMI grade 3 flow who were at a particularly low risk of adverse outcomes. The risk of in-hospital mortality increased in a stepwise fashion from 0.0% (n=41) in patients with a 90-minute CTFC that was faster than the 95% CI for normal flow (0 to 13 frames, hyperemia, TIMI grade 4 flow), to 2.7% (n=18 of 658 patients) in patients with a CTFC of 14 to 40 (a CTFC of 40 has previously been identified as the cutpoint for distinguishing TIMI grade 3 flow), to 6.4% (35/549) in patients with a CTFC >40 ( P =0.003). Although the risk of death, recurrent myocardial infarction, shock, congestive heart failure, or left ventricular ejection fraction ≤40% was 13.0% among patients with TIMI grade 3 flow (CTFC ≤40), the CTFC tended to segregate patients into lower-risk (CTFC ≤20, risk of adverse outcome of 7.9%) and higher-risk subgroups (CTFC >20 to ≤40, risk of adverse outcome of 15.5%; P =0.17).

Conclusions —Faster (lower) 90-minute CTFCs are related to improved in-hospital and 1-month clinical outcomes after thrombolytic administration in both univariate and multivariate models. Even among those patients classified as having normal flow (TIMI grade 3 flow, CTFC ≤40), there may be lower- and higher-risk subgroups.

Background— Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine expressed widely by vascular cells. However, scant in vivo evidence supports direct participation of MIF in atherogenesis. Therefore, we investigated whether deficiency of MIF modulates atherosclerotic lesion formation and composition in low-density lipoprotein receptor-deficient (LDLr ^−/− ) mice.

Methods and Results— MIF ^−/− LDLr ^−/− and LDLr ^−/− mice were generated and consumed an atherogenic diet for 12 or 26 weeks. MIF ^−/− LDLr ^−/− mice had significantly reduced abdominal aorta lipid deposition and intimal thickening from aortic arch throughout the abdominal aorta compared with LDLr ^−/− mice. Marked retardation of atherosclerosis over time in MIF-deficient mice accompanied decreased lesion cell proliferation. At 26 weeks, 20% of MIF-deficient mice developed only early, fatty streak-like lesions, whereas >80% of LDLr ^−/− mice developed advanced lesions containing calcification and lipid cores. Analysis of smooth muscle cells from mouse aortae demonstrated that MIF deficiency reduced smooth muscle cell proliferation, cysteine protease expression, and elastinolytic and collagenolytic activities.

Conclusions— Deficiency of MIF reduces atherogenesis in LDLr ^−/− mice. These results provide novel insight into inflammatory pathways operating in atheromata and identify a new potential target for modulating atherogenesis.

In this presentation stress has been laid upon the concept that the treatment, as well as the prognosis of chronic cor pulmonale depend upon the underlying pulmonary disease. It has long been known that the chief causes of chronic cor pulmonale are chronic obstructive pulmonary emphysema and various forms of fibrosis, particularly the pneumoconioses. An understanding of the difference between these diseases, both as to their pulmonary dysfunction and their circulatory complications, is crucial to success in therapy. Management of the patient with chronic pulmonary emphysema and (or pulmoniale is quite different from that of the subject with fibrosis and right heart involxemenit.

Unfortuniately, little as yet is known about the circulation in the pulmonary fibroses. In patients with pulmonary fibrosis as well as those with granulomas of the lung it would appear that the anatomic pulmonary lesion is chiefly responsible for the pulmonary hypertension, in contradistinction to the patients with emphysema. Inasmuch as the anatomic lesions are for the most part irreversible, so is the pulmonary hypertension. This has limited our therapeutic approach in this form of chronic cor pulmonale to rigorous restriction of physical activity directed at minimizing exacerbations of pulmonary hypertension.

While emphasis has been placed upon the difference in management of the patient with emphysema or fibrosis and cor pulmonale, nonetheless it should be remembered that in any individual patient these two conditions may coexist. In that event, intensive therapy directed at the sequellae of emphysema may be very rewarding.

Background Vascular myocyte apoptotic cell death has been reported in human atherectomy and endarterectomy specimens and for neointimal smooth muscle cells (SMCs) in balloon-injured rat carotid arteries between 7 and 30 days after injury. However, the immediate effect of balloon injury on medial SMC viability has not been examined.

Methods and Results Rat carotid arteries were harvested at the time of balloon injury (T=0) and at 0.5, 1, 2, and 4 hours after injury. Uninjured vessels or vessels harvested at the time of injury (T=0) did not display evidence of apoptosis. However, as early as 30 minutes after injury, 70% of medial SMCs appeared apoptotic by TdT-mediated dUTP nick end labeling (TUNEL) analysis and by the appearance of condensed chromatin. High frequencies of TUNEL-positive cells were also observed at 1 and 2 hours after injury but not at 4 hours. Transmission electron microscopy revealed many cells with morphological characteristics of apoptosis in the injured sections. A marked decrease in bcl-X expression was detected in the most luminal layers of the media. To corroborate these findings in a second animal model, rabbit external iliac arteries were analyzed after balloon angioplasty. Apoptotic cell death was evident in rabbit arteries at 30 minutes and at 4 hours after injury.

Conclusions As early as 30 minutes after balloon injury, myocytes appear to undergo apoptotic cell death at a high frequency as shown by TUNEL staining, chromatin condensation, and the appearance of morphological features in electron micrographs. The induction of apoptosis coincides with a marked downregulation of bcl-X expression.

Background— Red blood cell transfusion can both benefit and harm. To inform decisions about transfusion, we aimed to quantify associations of transfusion with clinical outcomes and cost in patients having cardiac surgery.

Methods and Results— Clinical, hematology, and blood transfusion databases were linked with the UK population register. Additional hematocrit information was obtained from intensive care unit charts. Composite infection (respiratory or wound infection or septicemia) and ischemic outcomes (myocardial infarction, stroke, renal impairment, or failure) were prespecified as coprimary end points. Secondary outcomes were resource use, cost, and survival. Associations were estimated by regression modeling with adjustment for potential confounding. All adult patients having cardiac surgery between April 1, 1996, and December 31, 2003, with key exposure and outcome data were included (98%). Adjusted odds ratios for composite infection (737 of 8516) and ischemic outcomes (832 of 8518) for transfused versus nontransfused patients were 3.38 (95% confidence interval [CI], 2.60 to 4.40) and 3.35 (95% CI, 2.68 to 4.35), respectively. Transfusion was associated with increased relative cost of admission (any transfusion, 1.42 times [95% CI, 1.37 to 1.46], varying from 1.11 for 1 U to 3.35 for >9 U). At any time after their operations, transfused patients were less likely to have been discharged from hospital (hazard ratio [HR], 0.63; 95% CI, 0.60 to 0.67) and were more likely to have died (0 to 30 days: HR, 6.69; 95% CI, 3.66 to 15.1; 31 days to 1 year: HR, 2.59; 95% CI, 1.68 to 4.17; >1 year: HR, 1.32; 95% CI, 1.08 to 1.64).

Conclusions— Red blood cell transfusion in patients having cardiac surgery is strongly associated with both infection and ischemic postoperative morbidity, hospital stay, increased early and late mortality, and hospital costs.

Background: Although cardiovascular health (CVH), especially health behaviors among youth and young adults, has been well-studied in the United States, similar research is limited in Vietnam. This study assesses the prevalence of various CVH behaviors—including ideal sleep health (ISH), ideal body mass index (IBMI), ideal physical activity (IPA), and non-smoking status—and identifies factors associated with these behaviors among medical students at the University of Danang, Vietnam (UD).

Methods: We used cross-sectional data from a health survey conducted in March-April 2024, targeting all medical students at UD (Years 1-6) with a 98% response rate. Definitions of CVH behaviors were detailed in the Table's footnotes. Multivariable logistic regression was employed for analysis. Demographic information, depression and anxiety levels, other lifestyle factors, and living environment conditions were included in the models. Differences in determinants by sex were also examined.

Results: Among 510 students (mean age 21.9 years; 51.4% female), 27.1% reported ISH, 19.8% achieved IPA, 61.2% had IBMI, 17.3% were underweight, and 96.3% were non-smokers. Multivariable regression indicated that age, anxiety levels, noise at night, and uncomfortable sleep space were associated with lower odds of ISH; odds ratios (95% confidence intervals) were 0.78 (0.68, 0.88), 0.99 (0.87, 0.99), 0.55 (0.35, 0.89), and 0.26 (0.11, 0.64), respectively. For other ideal behaviors, compared to males, females were significantly less likely to achieve IPA but more likely to have IBMI and be non-smokers (see Table). In gender-stratified analyses, working for pay was positively associated with IPA for females but negatively for males. Among females, better academic achievement was linked to a lower likelihood of IPA. Male students with less gaming time were more likely to be non-smokers.

Conclusion: Ideal sleep health, BMI, and physical activity levels are low, while non-smoking rate is high among medical students in Danang, Vietnam. Key determinants of sleep health include age, mental health, and living environments. Factors such as working for pay, academic achievement, and time spent gaming link to other CVH behaviors differently for males and females. More comprehensive studies on cardiovascular health in Vietnamese college students are needed to identify effective interventions for improving cardiovascular health in the young adult population of this developing country.

Introduction: Peripheral arterial disease (PAD) is a common condition among older adults. While many patients are asymptomatic, a substantial proportion experience intermittent claudication or critical limb ischemia and require revascularization or bypass surgery. PAD has also been associated with higher rates of cardiovascular and all-cause mortality. Estimates of the prevalence of PAD are essential to a complete understanding of the burden of atherosclerotic disease. We produced national and global estimates of PAD as part of the Global Burden of Disease 2016 Study.

Methods: We used national health surveys which assessed ankle-brachial index, commercial insurance claims databases, and published literature on population-based studies as input data. Our analyses corrected for readmission rates and variation in the use of diagnosis codes. Geospatial disease meta-regression software (DisMod-MR 2.1) was used to generate models separately by sex, location, and year to produce consistent estimates of prevalence. Uncertainty intervals (UI) were estimated using 1000 draws from the posterior distribution of each model. A country-level socio-demographic index (SDI), combining national income per capita, mean years of schooling, and total fertility rate, was used to examine disease burden by level of development.

Results: In 1990, there were an estimated 395 (95%UI: 345 to 453) million prevalent cases of PAD globally in women and 265 (95%UI: 231 to 307) million cases in men. By 2016, these numbers had increased to 695 (95%UI: 613 to 797) million cases in women and 506 (95%UI: 444 to 583) million cases in men. Age-standardized global rates in 1990 were 2106 (95%UI 1847 to 2415) per 100,000 and 1773 (95%UI: 1561 to 2037) per 100,000 in women and men, respectively. In 2016, these rates were 1930 (95%UI: 1702 to 2202) per 100,000 for women and 1658 (95%UI: 1457 to 1900) per 100,000 for men. The largest change in total number of prevalent cases from 1990 to 2016 was seen in middle-SDI countries with a 136% (95%UI: 131% to 137%) change in women and 140% (95%UI: 137% to 143%) change in men, indicating that the overall atherosclerotic burden in these countries is increasing. Comparisons indicate that these changes are largely being driven by population aging in high-SDI countries and by population growth in other locations.

Conclusions: The prevalence of PAD is increasing worldwide, with large increases in low- and middle-SDI countries in particular. These estimates of prevalence provide important estimates of the number of people who may benefit from medical therapies to reduce cardiovascular events.