What may be happen after an organophosphate exposure: Acute myocardial infarction?

The increase in accidental organophosphate poisoning as well as the rise in the number of cases of suicide attempts with organophosphate compounds is due to primarily to the widespread use of these compounds in agriculture. Organophosphates are anti-acetycholinesterase agents and their toxicity affects many organs, including the pancreas, liver and heart. Cardiac complications often accompany poisoning with these compounds and may be serious and often fatal. However, little is known about the myocardial infarction risk associated with exposure to pesticides. Herein, a rare case of acute myocardial infarction due to acute exposure to organophosphate compound is documented with electrocardiogram, enzyme and clinical characteristics in this report.     

Effects of preinfarction angina on no-reflow phenomenon after percutaneous coronary intervention in patients with acute myocardial infarction

Effects of preinfarction angina on no-reflow phenomenon after percutaneous coronary intervention in patients with acute myocardial infarction@王荣英$河北医科大学第二医院!石家庄050000 0311-70469016011     

A comparative study on transradial vs transfemoral artery access for primary percutaneous coronary intervention in patients with acute myocardial infarction

A comparative study on transradial vs transfemoral artery access for primary percutaneous coronary intervention in patients with acute myocardial infarction!050000$河北医科大学第二医院河北医科大学心脏介入中心@傅向华     

A randomized trail comparing primary percutaneous coronary intervention with a strategy of short-acting thrombolysis and immediate planned primary percutaneous coronary intervention in acute myocardial infarction

A randomized trail comparing primary percutaneous coronary intervention with a strategy of short-acting thrombolysis and immediate planned primary percutaneous coronary intervention in acute myocardial infarction!050000$河北医科大学第二医院河北医科大学心脏介入中心@傅向华     

Lactic acid and exercise performance : culprit or friend?

This article critically discusses whether accumulation of lactic acid, or in reality lactate and/or hydrogen (H+) ions, is a major cause of skeletal muscle fatigue, i.e. decline of muscle force or power output leading to impaired exercise performance. There exists a long history of studies on the effects of increased lactate/H+ concentrations in muscle or plasma on contractile performance of skeletal muscle. Evidence suggesting that lactate/H+ is a culprit has been based on correlation-type studies, which reveal close temporal relationships between intramuscular lactate or H+ accumulation and the decline of force during fatiguing stimulation in frog, rodent or human muscle. In addition, an induced acidosis can impair muscle contractility in non-fatigued humans or in isolated muscle preparations, and several mechanisms to explain such effects have been provided. However, a number of recent high-profile papers have seriously challenged the 'lactic acid hypothesis'. In the 1990s, these findings mainly involved diminished negative effects of an induced acidosis in skinned or intact muscle fibres, at higher more physiological experimental temperatures. In the early 2000s, it was conclusively shown that lactate has little detrimental effect on mechanically skinned fibres activated by artificial stimulation. Perhaps more remarkably, there are now several reports of protective effects of lactate exposure or induced acidosis on potassium-depressed muscle contractions in isolated rodent muscles. In addition, sodium-lactate exposure can attenuate severe fatigue in rat muscle stimulated in situ, and sodium lactate ingestion can increase time to exhaustion during sprinting in humans. Taken together, these latest findings have led to the idea that lactate/H+ is ergogenic during exercise.It should not be taken as fact that lactic acid is the deviant that impairs exercise performance. Experiments on isolated muscle suggest that acidosis has little detrimental effect or may even improve muscle performance during high-intensity exercise. In contrast, induced acidosis can exacerbate fatigue during whole-body dynamic exercise and alkalosis can improve exercise performance in events lasting 1-10 minutes. To reconcile the findings from isolated muscle fibres through to whole-body exercise, it is hypothesised that a severe plasma acidosis in humans might impair exercise performance by causing a reduced CNS drive to muscle.     

Myocardial sympathetic innervation in patients with chronic coronary artery disease: is reduction in coronary flow reserve correlated with sympathetic denervation?

Purpose Higher sensitivity of sympathetic nerves to ischaemia in comparison with myocytes has been observed and has been claimed to contribute to poor prognosis in patients with coronary artery disease (CAD). The aim of this study was to evaluate the dependency of myocardial sympathetic innervation on restrictions in coronary flow reserve (CFR). Methods We analysed 27 non-diabetic patients with advanced CAD. We determined quantitative myocardial blood flow using ¹³N-ammonia PET, myocardial viability with ¹⁸F-FDG PET and cardiac innervation with ¹¹C-HED PET. Scarred segments were excluded from analysis. We investigated the relationship between regional HED retention, blood flow and CFR. Results There was no correlation between rest perfusion and HED retention within a flow range from approximately 30 to 120 ml/(100 ml·min). A slight correlation was observed between stress perfusion values and HED retention (p<0.001), and between CFR and HED retention (p<0.001). Conclusion In non-diabetic CAD patients, HED retention in vital myocardium does not correlate with myocardial rest perfusion over a large flow range. The observed relation between HED retention and CFR indicates that sympathetic innervation can be preserved even when there is major impairment of myocardial blood supply. Most probably the occurrence of denervation depends not only on reductions in CFR, but also on the duration and severity of resulting ischaemic episodes.     

The optimal reference population for cardiac normality in myocardial SPET in the detection of coronary artery stenoses: patients with normal coronary angiography or subjects with low likelihood of coronary artery disease?

Both subjects with a low likelihood for coronary artery disease (CAD) and patients with normal findings on coronary angiography have been used as reference populations in non-invasive stress testing, including myocardial perfusion scintigraphy. Both of these criteria of normality - low likelihood of CAD and normal coronary angiography - have been criticised, and consensus on this issue is lacking. The aim of this study was to compare two different reference populations by testing the performance of artificial neural networks designed to interpret myocardial scintigrams. The networks were trained on myocardial perfusion scintigrams from 87 patients with angiographically documented CAD and on studies from one of two different reference groups: 48 patients with no signs of CAD based on angiography or 128 healthy volunteers with a likelihood for CAD <5%. The performance of the two different networks was then tested using scintigrams from a separate test group of 68 patients. Coronary angiography was used as the gold standard in this group. The network trained on patients with no signs of CAD based on angiography showed an area under the receiver operating characteristic (ROC) curve of 93%. The ROC area for the network trained on healthy volunteers was 72%, and this difference was statistically significant (P=0.03). The results of this study using artificial neural networks suggest that normal angiography should be preferred as the reference standard in myocardial scintigraphy when a patient is examined for CAD prior to possible angiography. Whether the same is true for other indications, e.g. in prognostic evaluation, is unknown.     

The optimal reference population for cardiac normality in myocardial SPET in the detection of coronary artery stenoses: patients with normal coronary angiography or subjects with low likelihood of coronary artery disease?

Both subjects with a low likelihood for coronary artery disease (CAD) and patients with normal findings on coronary angiography have been used as reference populations in non-invasive stress testing, including myocardial perfusion scintigraphy. Both of these criteria of normality--low likelihood of CAD and normal coronary angiography--have been criticised, and consensus on this issue is lacking. The aim of this study was to compare two different reference populations by testing the performance of artificial neural networks designed to interpret myocardial scintigrams. The networks were trained on myocardial perfusion scintigrams from 87 patients with angiographically documented CAD and on studies from one of two different reference groups: 48 patients with no signs of CAD based on angiography or 128 healthy volunteers with a likelihood for CAD <5%. The performance of the two different networks was then tested using scintigrams from a separate test group of 68 patients. Coronary angiography was used as the gold standard in this group. The network trained on patients with no signs of CAD based on angiography showed an area under the receiver operating characteristic (ROC) curve of 93%. The ROC area for the network trained on healthy volunteers was 72%, and this difference was statistically significant (P=0.03). The results of this study using artificial neural networks suggest that normal angiography should be preferred as the reference standard in myocardial scintigraphy when a patient is examined for CAD prior to possible angiography. Whether the same is true for other indications, e.g. in prognostic evaluation, is unknown.     

Effects of primary PCI and facilitated PCI on myocardial viability and ventricular systolic synchrony in acute myocardial infarction patients

Effects of primary PCI and facilitated PCI on myocardial viability and ventricular systolic synchrony in acute myocardial infarction patients!石家庄050000$河北医科大学第二医院@谷新顺 !石家庄050000$河北医科大学第二医院@傅向华 !石家庄050000$河北医科大学第二医院@马宁     

Nuclear myocardial perfusion imaging with a cadmium–telluride semiconductor detector gamma camera in patients with acute myocardial infarction

Objective

Since myocardial perfusion imaging (MPI) with conventional sodium iodine (NaI) device has low spatial resolution, there have been some cases in which small structures such as non-transmural myocardial infarction could not be properly detected. The purpose of this study was to evaluate potential usefulness of cadmium–telluride (CdTe) semiconductor detector-based high spatial resolution gamma cameras in detecting myocardial infarction sites, especially non-transmural infarction.

Methods

A total of 38 patients (mean age ± SD: 64 ± 21 year) who were clinically diagnosed with acute myocardial infarction were included. Twenty-eight cases of them were with ST segment elevation myocardial infarction (STEMI) and 10 cases with non-ST segment elevation myocardial infarction (NSTEMI). In all patients, myocardial perfusion single photon emission computed tomography images were acquired with Infinia (NaI device) and R1-M (CdTe device), and the images were compared concerning the detectability of acute myocardial infarction sites.

Results

The detection rates of the myocardial infarction site in cases with STEMI were 100 % both by NaI and CdTe images. In cases with NSTEMI, detection rate by NaI images was 50 %, while that of CdTe images was 100 % (p = 0.033). The summed rest score (SRS) value derived from CdTe images was significantly higher than that from NaI images in cases with STEMI [NaI images: 12 (7–18) versus CdTe images: 14 (9–20)] (p < 0.001). SRS derived from CdTe images was significantly higher than that derived from NaI images in cases with NSTEMI [NaI images: 2 (0–5) versus CdTe images: 6 (6–8)] (p = 0.006).

Conclusions

These results indicate that MPI using CdTe-semiconductor device will provide a much more accurate assessment of acute myocardial infarction in comparison to current methods.     

Does coronary calcium score zero reliably rule out coronary artery disease in low-to-intermediate risk patients? A coronary CTA study

BackgroundObjective was to assess if coronary calcium score (CCS) zero (<1.0AU) reliably rules out coronary artery disease (CAD) by coronary CTA; and if a difference between CCS zero and ultralow CCS (0.1–0.9AU) exists.Methods6439 low-to-intermediate ASCVD-risk patients (57.9 ± 11.1 years; 44.4% females) who underwent CTA and CCS were enrolled. Coronary CTAs were evaluated for: (1) stenosis severity (CADRADS: <25%, 25–49%, 50–69%, 70–99%, and 100%), (2) mixed-plaque burden, and (3) high-risk-plaque-(HRP)-criteria. Primary endpoints were all-cause and cardiovascular (CV) mortality, secondary endpoint MACE.ResultsOverall 1451 (22.5%) had CCS<1.0 AU. Among them, 1289 had CCS zero and 162 ultralow CCS (0.1–0.9AU). In CCS zero patients, 25.9% had CAD, 5.1% > 50% and 20.8% less than 50% stenosis, 6.8% had HRP with min 2 criteria, respectively. LAP<30HU, LAP<60HU, Napkin-Ring-Sign, Spotty calcification and PR were found in 1.3%, 3.7%, 2.8%, 2.3% and 8.2%.CAD prevalence was with 87.7% markedly higher in the ultralow CCS (p < 0.001) group, >50% stenosis (16.6%), total plaque burden (p < 0.001) and HRP-criteria rates were higher (up to 19.1%) (p < 0.001, respectively).All-cause mortality was similar (2.7% and 1.9%) in CCS 0 and ultralow patients (mean follow-up 6.6 ± 4.2 years). Composite MACE (n = 7, 0.48%) was higher than CV-mortality (n = 1, 0.06%, p = 0.038, OR 1.08–1.6). More HRP were found on 128-slice-dual-source-CTA compared to 64-slice (p < 0.001). There were no differences in CTA findings between patients with and without chest pain, but more females were symptomatic.ConclusionEarly signs of CAD on CTA are frequent in CCS zero and even present in the majority of ultralow CCS (0.1–0.9AU) patients, who should not be downgraded to CCS zero patients. High-risk plaque and >50% stenosis rate is low but not negligible; and MACE rate very low.