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Aims
Impaired coronary microvascular dilatory function can lead to exercise induced myocardial ischemia and angina pectoris even in patients without significant (>50%) obstructive coronary atherosclerosis (APWOCA). Diffuse distal vessel epicardial spasm and microvascular spasm have been also proposed as a plausible explanation for angina at rest in these patients. However, objective systematic evidence for the latter i.e. echocardiographic wall motion abnormalities during angina, is lacking at present. Coronary epicardial and microvascular spasm can be triggered in susceptible patients by the administration of intracoronary acetylcholine (Ach). We sought to assess whether Ach induced diffuse distal epicardial coronary artery spasm (≥75% diameter reduction) and coronary microvascular spasm can cause transient ischemic left ventricular dysfunction, as assessed by echocardiography.Methods
50 patients (19 men aged 60.5 ± 8.9 years) with stable APWOCA were assessed for coronary spasm and myocardial ischemia with intracoronary Ach infusion, 2D transthoracic echocardiography (before and during Ach testing), continuous 12-lead ECG monitoring, and ultrasensitive cardiac troponin (US-cTn) measurement before and within 4 h after Ach testing.Results
14 patients (28%) had a “negative” Ach test, 14 (28%) developed coronary microvascular spasm and 17 (34%) had diffuse distal epicardial spasm. In 5 patients (10%) the test was inconclusive. Echocardiographic variables including deceleration time, EF slope and E/A, as well as ultrasensitive-cTn concentrations were abnormal during Ach induced ischemic ECG changes. Conclusions: We have, for the first time, demonstrated that Ach induced coronary microvascular spasm is associated with echocardiographic changes and ultrasensitive-cTn elevations, indicative of myocardial ischemia. 相似文献Objective
The purpose of this study was to evaluate the effect of weight loss induced in morbidly obese subjects by Roux-en-Y gastric bypass bariatric surgery on the atherogenic features of their plasma lipoproteins.Methods
Twenty-one morbidly obese subjects undergoing bariatric surgery were followed up for up to 1 year after surgery. Plasma and lipoproteins were assayed for chemical composition and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Lipoprotein size was assessed by non-denaturing polyacrylamide gradient gel electrophoresis, and oxidised LDL by ELISA. Liver samples were assayed for mRNA abundance of oxidative markers.Results
Lipid profile analysis revealed a reduction in the plasma concentrations of cholesterol and triglycerides, which were mainly associated with a significant reduction in the plasma concentration of circulating apoB-containing lipoproteins rather than with changes in their relative chemical composition. All patients displayed a pattern A phenotype of LDL subfractions and a relative increase in the antiatherogenic plasma HDL-2 subfraction (>2-fold; P < 0.001). The switch towards predominantly larger HDL particles was due to an increase in their relative cholesteryl ester content. Excess weight loss also led to a significant decrease in the plasma concentration of oxidised LDL (∼−25%; P < 0.01) and in the total Lp-PLA2 activity. Interestingly, the decrease in plasma Lp-PLA2 was mainly attributed to a decrease in the apoB-containing lipoprotein-bound Lp-PLA2.Conclusion
Our data indicate that the weight loss induced by bariatric surgery ameliorates the atherogenicity of plasma lipoproteins by reducing the apoB-containing Lp-PLA2 activity and oxidised LDL, as well as increasing the HDL-2 subfraction. 相似文献Median age at diagnosis of lung cancer is 70 years. Its presentation in patients 40 or younger is uncommon and it has been proposed that maybe it is a different disease due to its clinical characteristics and genetic makeup. There are a limited number of studies in this population and they report different clinic-pathological characteristics in comparison with older patients.
MethodsWe described the incidence of lung cancer patients diagnosed at age 40 or younger at the Instituto Nacional de Enfermedades Neoplasicas (INEN), Lima-Peru; from 2009 to 2017 and evaluated the characteristic of NSCLC. Epidemiologic and clinic-pathological data was collected from clinical files. Analysis was carried out using SPSSvs19 software.
ResultsWe identified 3823 patients with lung cancer seen at INEN during the study period. Among these, 166 (4.3%) patients were 40 years or younger, and 137/166 (82.5%) were NSCLC. Median age at diagnosis was 36 years (range 14–40 years) and 59.1% of patients were female. A smoking history was present in 14.4% of patients. Frequent symptoms at diagnosis were cough (62.0%), chest pain (51.8%) and dyspnea (40.9%). Adenocarcinoma was the most common histological type (63.3%). Most patients had advanced disease at diagnosis (84.7%). The median overall survival was 8.2 months.
ConclusionsThe proportion of young patients with lung cancer in our population is higher than that reported in the most recent literature. Lung cancer in the young is mostly sporadic, more frequent in women, usually adenocarcinoma type and it presents with advanced disease, resulting in a very poor survival.
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