Prevalence of elevated lipoprotein(a) in cardiac rehabilitation patients - results from a large-scale multicentre registry in Germany

BACKGROUND

Lipoprotein(a) (Lp(a)) is an independent risk factor for myocardial infarction and aortic valve stenosis. European guidelines recommend assessing it at least once in a lifetime, particularly in premature atherosclerotic heart disease.

METHODS

A non-interventional registry was conducted at MEDIAN rehabilitation facilities in Germany to assess the frequency of Lp(a) testing in referring acute care hospitals and the prevalence of elevated Lp(a) levels in aortic valve stenosis or premature myocardial infarction. All consecutive patients referred after coronary intervention or aortic valve surgery were included in four cohorts: aortic valve intervention (cohort 1), current/previous myocardial infarction at < 60 years of age (cohorts 2a/2b), and myocardial infarction at ≥ 60 years of age (control).

RESULTS

The analysis included 3393 patient records (cohort 1, n = 1063; cohort 2a, n = 1351; cohort 2b, n = 381; control, n = 598). Lp(a) had been determined at the referring hospital in 0.19% (cohort 1), 4.96% (cohort 2a), 2.36% (cohort 2b), and 2.01% (control) of patients. Lp(a) levels were > 50 mg/dL or > 125 nmol/L in 28.79% (cohort 1), 29.90% (cohort 2a), and 36.48% (cohort 2b; p < 0.001) compared to 24.25% (control). Family history of premature cardiovascular disease was reported in 13.45% (cohort 1), 38.56% (cohort 2a), and 32.81% (cohort 2b) compared to 17.89% (control; p < 0.05 for each comparison).

CONCLUSIONS

Lp(a) had been rarely assessed in acute management of aortic valve stenosis or premature myocardial infarction despite expanding scientific evidence and guideline recommendation. Given the above-average incidence of elevated Lp(a) levels, awareness for Lp(a) has to increase substantially to better identify and manage high-risk patients.

Development of the prosencephalic structures, ganglionic eminence, basal ganglia and thalamus at 11 + 3 to 13 + 6 gestational weeks on 3D transvaginal ultrasound including normative data

OBJECTIVES

To show the development of ganglionic eminence, basal ganglia and thalamus/hypothalamus in week 11 + 3 to 13 + 6 by transvaginal 3D ultrasound.

METHODS

To visualize the prosencephalic structures surrounding the 3rd ventricle, 285 three-dimensional ultrasound volume blocks from 402 fetuses examined were selected in a prospective transvaginal 3D study to compare ultrasound images of ganglionic eminence, basal ganglia, thalamus/hypothalamus with embryological sections. In addition, measurements of the described structures were made in 104 fetuses to quantify the embryological development.

RESULTS

The sonomorphologic characteristics of ganglionic eminence, basal ganglia and thalamus/hypothalamus are described in 71% of the fetuses examined. Measurements of the structures in 57% of the fetuses, show the following results: axGE ap = 0.17 + 0.112*CRL; axGE/I = 0.888 + 0.048*CRL; axGE/BG = 0.569 + 0.041*CRL; coGE/BG = 0.381 + 0.048*CRL; coTh lat = - 0.002 + 0.135*CRL; coTh/HyT = 3.68 + 0.059*CRL; co3.V lat = 0.54 + 0.008*CRL.

CONCLUSION

Transvaginal 3D neurosonography allows visualization and measurement of normal structures in the fetal prosencephalon at 11 + 3 to 13 + 6 weeks of gestation (GW) including details of ganglionic eminence (GE), basal ganglia (BG), and thalamus/hypothalamus (Th/HyT). Further scientific work is needed before using the results to decide on pathological changes in patients.

[Late neurological consequences of a SARS-CoV-2 infection]

BACKGROUND

Persistent neurological late symptoms of SARS-CoV-2 infection are common and require regular follow-up treatment. In order to establish uniform therapy concepts, it is necessary to evaluate individual therapeutic approaches for long COVID and post-COVID-19 syndrome.

ANAMNESE

A 62-year-old patient was admitted to our rehab clinic for follow-up treatment after severe SARS-CoV-2 infection with neurological symptoms. The initially extensive laboratory and imaging investigation did not reveal any organic cause for the sometimes apoplectiform, complex clinical picture, so that the patient was transferred directly to our rehabilitation clinic in the event of everyday restrictions and rollator dependency.

EXAMINATION AND FINDINGS

Clinically, there was a reduced general condition and the mood was depressed. Neurological symptoms were gait ataxia, hand tremor, amnesic aphasia and reduced ability to concentrate. PET / CT showed no evidence of tumor or inflammation.

THERAPY AND PROGRESS

A multimodal therapy program consisting of physiotherapy and occupational therapy as well as psychological support was carried out. In addition, off-label therapy with oral glucocorticoids and colchicine was initiated. In the course of the disease, there was a clear reduction in all symptoms with little residual hand tremor.

CONCLUSIONS

Whole body and brain FDG PET can be helpful in long COVID and post-COVID-19 syndrome patients with neurological symptoms of unknown origin. These patients benefit from systematic rehabilitation. Glucocorticoids and colchicine appear to accelerate symptom reduction. The rehabilitative therapy should be continued on an outpatient basis.

Influence of tissue affinity of angiotensin-converting enzyme inhibitors on left ventricular remodeling after myocardial infarction

BACKGROUND

The demonstration of local renin-angiotension systems has raised the question of whether angiotensin-converting enzyme (ACE) inhibitors with different tissue affinities differ with regard to their effects on postinfarction remodeling.

HYPOTHESIS

The study was undertaken to investigate the influence of ACE inhibitors with different tissue affinity on morphology and function of the infarcted left ventricle.

METHODS

In all, 52 patients (17 women, 35 men, 38-73 years) with large acute myocardial infarction were randomized to receive either 25-75 mg/day captopril or 10-20 mg/day fosinopril beginning on the Day 7 after infarction. Of these, 28 had anterior and 24 had posterior wall infarctions. Infarct size was determined by the creatine kinase integral method. Fifty patients were examined by cinemagnetic resonance imaging (CMRI) 1 and 26 weeks after infarction. The following parameters were determined: left ventricular end-diastolic and end-systolic volume index (LVEDVI, LVESVI), ejection fraction (LVEF), infarct weight, and muscle mass (LVMM). The volume-to-mass ratio (VMR) was calculated and the clinical status according to the guidelines of the New York Heart Association (NYHA) was documented at each examination time. The results were compared with those of a historical sample without ACE-inhibitor therapy examined in an identical manner (n = 31, 10 women, 21 men, 36-75 years).

RESULTS

LVEDVI and LVESVI increased in the first 6 months after infarction by 24.9 and 36.6%, respectively, in the historical sample; by 11.0 and 7.8%, respectively, under captopril; and by 13.1 and 10.7%, respectively, under fosinopril. LVEF decreased by 14.9% in the untreated sample, by 3.7% under captopril and by 5.0% under fosinopril. Infarct weight and LVMM increased by 12.7 and 15.3%, respectively, without ACE inhibition, by 5.7 and 10.1%, respectively, in patients treated with captopril, and by 6.1 and 9.3%, respectively, in patients treated with fosinopril. The VMR increased by 7.4% in the historical sample, by 3.5% in the captopril group, and by 1.8% in the fosinopril group. The NYHA clinical status improved by 18.2% without ACE inhibition, by 42.9% in the captopril group, and by 26.3% in the fosinopril group. The differences between the two ACE-inhibitor groups and the reference group were all significant, while the differences between the captopril group and the fosinopril group were significant only for VMR (p < 0.01) and NYHA class (p < 0.05).

CONCLUSIONS

Both captopril and fosinopril have a comparable positive influence on postinfarction remodeling and on clinical status. Lipophilicity and tissue affinity do not seem to play a clinically important role in ACE-inhibitor therapy after infarction.

Determinants of coronary blood flow in humans: quantification by intracoronary Doppler and ultrasound

The direct determinants of coronary flow are lumen area and blood flow velocity; however, the precise mechanisms that control these factors are not fully understood. The aim of the present study was to assess by which mechanisms lumen area and coronary flow velocity interact with hemodynamic and morphometric factors, thereby influencing coronary flow. Intracoronary Doppler and ultrasound measurements were performed in 28 patients without coronary lumen irregularities. Flow velocity and lumen cross-sectional area were measured in the proximal segments of all three coronary arteries. Global lumen cross-sectional area and global flow were obtained by adding up the values of all three coronary arteries. Left ventricular mass was assessed by echocardiography. Stress-mass-heart rate and pressure-rate products reflecting myocardial oxygen demand were calculated. Global coronary flow increased during adenosine-induced hyperemia from 197 +/- 72 to 637 +/- 204 ml/min (P < 0.001). Global coronary flow closely correlated with the stress-mass-heart rate product (r = 0.62; P < 0.001). Looking at the two constituents of flow separately, global coronary cross-sectional area was closely related to left ventricular muscle mass (r = 0.61; P < 0.001), whereas mean coronary flow velocity at rest showed a strong linear relation with the pressure-rate product (r = 0.64; P < 0.001). There was no interaction between cross-sectional area and blood flow velocity in any of the coronary vessels. Coronary lumen size and flow velocity, the two determinants of coronary flow, are principally determined by different physiological factors. Long-term flow adaptation is achieved by an increase in coronary lumen size, whereas short-term myocardial oxygen requirements are met by changes in resting flow velocity.

Cognitive modulation of the cerebral processing of human oesophageal sensation using functional magnetic resonance imaging

BACKGROUND

While cortical processing of visceral sensation has been described, the role that cognitive factors play in modulating this processing remains unclear.

AIM

To investigate how selective and divided attention modulate the cerebral processing of oesophageal sensation.

METHODS

In seven healthy volunteers (six males, mean age 33 years; ranging from 24 to 41 years old) from the general community, phasic visual and oesophageal (non-painful balloon distension) stimuli were presented simultaneously. During the selective attention task, subjects were instructed to press a button either to a change in frequency of oesophageal or visual stimuli. During a divided attention task, subjects received simultaneous visual and oesophageal stimuli and were instructed to press a button in response to a change in frequency of both stimuli.

RESULTS

Selectively focussing attention on oesophageal stimuli activated the visceral sensory and cognitive neural networks (primary and secondary sensory cortices and anterior cingulate cortex respectively) while selective attention to visual stimuli primarily activated the visual cortex. When attention was divided between the two sensory modalities, more brain regions in the sensory and cognitive domains were utilised to process oesophageal stimuli in comparison to those employed to process visual stimuli (p=0.003).

CONCLUSION

Selective and divided attention to visceral stimuli recruits more neural resources in both the sensory and cognitive domains than attention to visual stimuli. We provide neurobiological evidence that demonstrates the biological importance placed on visceral sensations and demonstrate the influence of cognitive factors such as attention on the cerebral processing of visceral sensation.

Genetic variation of the platelet- surface integrin GPIIb-IIIa (PIA1/A2-SNP) shows a high association with Type 2 diabetes mellitus

AIMS/HYPOTHESIS

The gene encoding the beta(3)-subunit (GPIIIa) of the platelet alpha(2)beta(3)-integrin (fibrinogen receptor) shows a polymorphism PlA1/A2 with the A2 allele putatively associated with an increased risk of acute ischaemic events. This study investigated whether Type 2 diabetes as a particular macrovascular risk factor associates with the thrombogenic PIA2 genotype.

METHODS

The PlA genotype was determined in 112 consecutive Type 2 diabetic patients additionally classified according to the presence of macrovascular disease. Forty-four non-diabetic patients with angiografically documented cardiovascular disease (CAD/ AMI) and a further 59 non-diabetic subjects with no angiografical signs of CAD were investigated as genomic background control (n=103). PIA-genotyping was carried out by standard restriction fragment length analysis (RFLA) of PCR amplified lymphocyte template DNA.

RESULTS

The overall allelic PlA2- prevalence accounted to 34.8% (39/112) in diabetic patients as compared to 14.6% (15/103) in non-diabetic patients [OR 3.1 (1.6-6.1), p<0.01]. This odds ratio increased to 7.0 (2.5-19.7), (p<0.01) in subjects free of criteria of macrovascular disease. In non-diabetic control subjects without CAD there was an allelic PIA2 frequency of 10.2% (6/59) as compared to 20.5% (9/44) in patients with CAD and a history of AMI being less than either diabetes subgroup. The PIA2 prevalence in the subgroup of diabetes patients with macrovascular complications did not differ from the respective value in patients without macrovascular disease. [29.0% (20/69) vs. 44.2% (19/43)].

CONCLUSION/INTERPRETATION

This study confirms a trendwise association of PlA2 with severe coronary artery disease, but rather suggests an even stronger, highly significant association with the metabolic condition of Type 2 diabetes mellitus. This justifies the speculation that pathways dependent on the platelet alpha(2)beta(3) integrin physiology could be implicated in the pathogenesis of Type 2 diabetes which lends further support to the "common soil" hypothesis of diabetes and vascular disease.

Sphingosylphosphorylcholine, a naturally occurring lipid mediator, inhibits human platelet function

1 The lysophospholipids, lysophosphatidic acid and sphingosine 1-phosphate, have been reported to activate platelets. Here we examined effects of the naturally occurring related sphingosylphosphorylcholine (SPC) on human platelet function. 2 Platelet activation was determined as aggregation, elevation of intracellular Ca(2+) concentrations, surface expression of P-selectin, GP 53, and GP IIb/IIIa neoepitope PAC-1, and of fibrinogen binding to the platelet surface. 3 Platelets were activated by ADP (5 and 20 micro M), the thrombin receptor-activating peptide TRAP-6 (5 and 20 micro M), the thromboxane A(2) mimetic U-46619 (1 micro M) and collagen (20 and 50 micro g ml(-1)) but not by SPC (up to 20 micro M). 4 SPC concentration-dependently (IC(50) approximately 1-10 micro M) inhibited activation of washed human platelets in response to all of the above agonists, with almost complete inhibition occurring at 20 micro M SPC. 5 The SPC stereoisomers, D-erythro SPC and L-threo SPC, exhibited similar concentration-response curves in inhibiting 20 micro M ADP-induced platelet aggregation, suggesting that SPC did not act via specific lysophospholipid receptors. 6 Although SPC slightly activated platelet protein kinase A (as assessed by VASP phosphorylation), this effect could not explain the marked platelet inhibition. Possible protein kinase C inhibition also did not explain the inhibition of platelet activation by SPC. On the other hand, SPC suppressed agonist-induced Ca(2+) mobilization and phospholipase C stimulation. 7 These results indicate that the lysophospholipid SPC is an effective inhibitor of human platelet activation, apparently primarily by uncoupling agonist-activated receptors from their effectors.

Comparison of signalling mechanisms involved in rat mesenteric microvessel contraction by noradrenaline and sphingosylphosphorylcholine

1 We have compared the signalling mechanisms involved in the pertussis toxin-sensitive and -insensitive contraction of rat isolated mesenteric microvessels elicited by sphingosylphosphorylcholine (SPC) and noradrenaline (NA), respectively. 2 The phospholipase D inhibitor butan-1-ol (0.3%), the store-operated Ca(2+) channel inhibitor SK>F 96,365 (10 microM), the tyrosine kinase inhibitor genistein (10 microM), and the src inhibitor PP2 (10 microM) as well as the negative controls (0.3% butan-2-ol and 10 microM diadzein and PP3) had only little effect against either agonist. 3 Inhibitors of phosphatidylinositol-3-kinase (wortmannin and LY 294,002, 10 microM each) or of mitogen-activated protein kinase kinase (PD 98,059 and U 126, 10 microM each) did not consistently attenuate NA- and SPC-induced contraction as compared to their vehicles or negative controls (LY 303,511 or U 124). 4 The phospholipase C inhibitor U 73,122 (10 microM) markedly inhibited the SPC- and NA-induced contraction (70% and 88% inhibition of the response to the highest NA and SPC concentration, respectively), whereas its negative control U 73,343 (10 microM) caused only less than 30% inhibition. 5 The rho-kinase inhibitors Y 27,632 (10 microM) and fasudil (30 microM) caused a rightward-shift of the NA concentration-response curve by 0.7-0.8 log units and reduced the response to 10 microM SPC by 88% and 83%, respectively. 6 These data suggest that SPC and NA, while acting on different receptors coupling to different G-protein classes, elicit contraction of rat mesenteric microvessels by similar signalling pathways including phospholipase C and rho-kinase.

eNOS 894T allele and coronary blood flow at rest and during adenosine-induced hyperemia

The 894T allele of a G894T polymorphism in the endothelial nitric oxide synthase (eNOS) gene is associated with decreased eNOS activity, cleavage of the protein, and endothelial dysfunction. The present study evaluated the association with coronary blood flow (CBF) at rest and during adenosine (ADO)-induced hyperemia. CBF was determined by Doppler flow wire and angiography in 97 left anterior descending arteries of individuals without coronary artery disease. At rest, average peak velocity (APV) was lower and coronary vascular resistance (CVR) was higher in homozygous carriers of the 894T allele than in heterozygotes and individuals without the 894T allele. CBF tended to be lower in eNOS 894T allele carriers. During ADO-induced hyperemia (18 microg ic), APV, CVR, and CBF were not statistically different between the genotypes. The reduced APV at rest in conjunction with an increased CVR indicates a vasomotor dysfunction related to an increased microvascular resting tone in eNOS 894T allele carriers.

Increased heterogeneity of coronary perfusion in patients with early coronary atherosclerosis

BACKGROUND

In patients with typical angina but angiographically normal coronary arteries, abnormal vasomotor function is assumed to be a major underlying cause. However, data on this issue are conflicting, and recent studies suggest that fluid dynamic abnormalities exist in these patients. The aim of the study was to evaluate whether early stages of atherosclerosis are characterized by alterations of baseline coronary hemodynamics and endothelium-independent vasomotion. Besides established intracoronary Doppler parameters, heterogeneity of perfusion was assessed and related to early signs of atherosclerosis as determined by electron-beam computed tomography (EBCT).

METHODS

In 59 patients with typical angina and angiographically normal or near-normal coronary arteries, intracoronary Doppler measurements were performed in all 3 major coronary arteries. Baseline average peak velocity (bAPV) and hyperemic average peak velocity (hAPV) in response to intracoronary injection of adenosine were measured, and coronary flow velocity reserve (CFVR) was calculated. Heterogeneity was assessed as variability of bAPV, hAPV, and CFVR and was calculated as (STD/MEAN). 100. Doppler data were analyzed according to tertiles of the EBCT-derived Agatston calcium score (ie, score 0-1 [lowest tertile], 2-28 [medium tertile], and >28 [highest tertile]).

RESULTS

The mean EBCT-derived Agatston calcium score was 49 +/- 107. No coronary calcium was observed in 17 (29%) patients. The mean values of bAPV, hAPV, and CFVR were not different between the calcium score tertiles. However, patients in the highest tertile had a significantly increased variability index of bAPV (29.6% +/- 11.6%) compared with patients in the lowest tertile (13.4% +/- 7.3%, P <.0001). Variability of CFVR was also increased in these patients (15.5% +/- 11.7% vs 10.5% +/- 4.0%, P =.03).

CONCLUSION

These results indicate that early stages of atherosclerosis are characterized by microvascular abnormalities that do not uniformly affect the myocardium but are heterogeneous. The high variability of baseline coronary flow velocity with increasing coronary calcium suggests that in patients with early stages of atherosclerosis fluid dynamic effects may play a crucial role even in the absence of angiographically appreciable epicardial stenoses.

Is the tissue affinity of ACE inhibitors of relevance for the remodeling of the left ventricular wall following myocardial infarction? Estimations with cine magnetic resonance imaging

BACKGROUND

Angiotensin-converting enzyme (ACE) inhibitors have been shown to be of value in the treatment of postinfarction remodeling. The question whether substances with a greater tissue affinity are associated with advantages for the acute and the chronic course is, however, still unclear.

AIM

The aim of the present study was to investigate the influence of ACE inhibitors with differing tissue affinities on the remodeling of the left ventricular wall in patients recovering from myocardial infarction.

METHODS

52 patients (17 women, aged 38-73 years) suffering their first acute myocardial infarction were randomized to receive a daily dose of either 25-75 mg captopril or 10-20 mg fosinopril, beginning on the 7th postinfarction day. 28 patients had an anterior wall infarction and 24 patients an inferior wall infarction. The size of the infarct was determined using the creatine kinase integral method. 50 patients were investigated by cine magnetic resonance imaging 1 and 26 weeks after the infarction. The following parameters were determined: infarct weight and diastolic diameter of the infarcted zone, systolic wall stress, muscle mass, diastolic and systolic diameters, systolic wall thickening, and motility of the noninfarcted myocardium.

RESULTS

The infarct weight increased under captopril by 5.7% (p < 0.05) and under fosinopril by 6.1% (p < 0.05). The diastolic diameter of the infarcted zone decreased by 12% under captopril (p < 0.001) and by 11% under fosinopril (p < 0.001). The systolic wall thickness increased by 12.1% (p < 0.001) and the muscle mass by 12.7% (p < 0.001) under captopril and by 15.4% (p < 0.001) and 9.6% (p < 0.01), respectively, under fosinopril. Under captopril, the diastolic diameter increased by 2.3% (p < 0.05) and the systolic diameter by 17.8% (p < 0.01) and under fosinopril by 2.8% (n.s.) and 17.5% (p < 0.001), respectively. The systolic wall thickening increased by 73.9% under captopril (p < 0.001) and by 129.4% under fosinopril (p < 0.001). The motility decreased by 13.8% (p < 0.05) under captopril and by 6.0% (n.s.) under fosinopril. For all parameters, the results seen in anterior wall infarction were appreciably poorer than those seen in inferior wall infarction. All the differences between captopril and fosinopril were not significant.

CONCLUSIONS

Captopril and fosinopril show no major differences in their influence on left ventricular wall remodeling following myocardial infarction. On the basis of the present results, the tissue affinity of an ACE inhibitor does not appear to be of a significant relevance for postinfarction treatment.

[Effect of ACE-inhibitors on left ventricular remodeling after acute anterior or posterior myocardial infarct. Cine- magnetic resonance tomography study]

The question whether patients with posterior infarctions (PMI) have a comparable benefit of an ACE-inhibitor therapy to those with anterior infarction (AMI) is still open. The study was undertaken to investigate the different influence of ACE inhibitors on the remodeling of the left ventricle after AMI or PMI. 52 patients (Pt.) (17 female, 38-73 years) were randomized to receive either 25-75 mg/day captopril (C) or 5-20 mg/day fosinopril (F) beginning on day 7 after acute myocardial infarction. 28 Pt. had AMI, 24 Pt. PMI. Infarct size was determined by the creatine kinase integral method. 50 Pt. were examined by cine magnetic resonance imaging 1 and 26 weeks after infarction. We determined: left ventricular end-diastolic (LVEDVI) and end-systolic (LVESVI) volume index, ejection fraction (EF), infarction weight (IW), left ventricular muscle mass (MM), systolic wall thickening (SWT) and motility (MOT) of the vital myocardium, and clinical behavior according to the guidelines of the New York Heart Association (NYHA). The results were compared with those of a sample (V) without ACE inhibitor therapy (10 females, 21 males, 36-75 years, 19 AMI, 12 PMI). There were no significant differences between C and F. Without ACE-inhibition therapy LVEDVI increased by 28.2% in AMI, by 18.4% in PMI (p < 0.001), with ACE-inhibition by 13.7% in AMI and by 9.9% in PMI (p < 0.001). LVESVI increased in V by 40.1% in AMI, by 28.5% in PMI (p < 0.001). With ACE-inhibitor we found an increase of 11.2% in AMI and 5.3% in PMI (p < 0.001). EF decreased without ACE-inhibitor by 18.7% in AMI and by 10.2% in PMI (p < 0.001), with ACE-inhibition increased by 4.3% in AMI and PMI, respectively (n. s.). NYHA got better in all groups, by 17.4% in AMI and 20.8% in PMI without ACE-inhibitor (n.s.), by 45.5% in AMI and 31.6% in PMI with ACE-inhibitor (p < 0.001). IG increased by 15.5% in AMI and 8.8% in PMI in V (p < 0.001), by 11.2% in AMI and 5.3% in PMI with C or F (p < 0.001). MM got bigger in V by 16.6% in AMI and 12.7% in PMI (p < 0.05), with ACE-inhibitor by 11.7% in AMI and 8.0% in PMI (p < 0.05). sWD increased by 12.9% in AMI and by 6.7% in PMI in V (p < 0.01), by 37.1% in AMI and 88.0% in PMI with C or F (p < 0.001). MOT decreased by 39.6% in AMI and 14.9% in PMI without ACE-inhibition (p < 0.001) and increased by 4.3% in AMI and by 5.0% in PMI with ACE-inhibitor (n. s.). All differences between V and the ACE-inhibitor groups were significant. Even patients with PMI clearly benefit from ACE-inhibitor therapy, but less than those with AMI. Captopril and fosinopril show no different effects after myocardial infarction.

Enhanced epinephrine-induced platelet aggregation in individuals carrying the G protein beta3 subunit 825T allele

The 825T allele of a common C825T polymorphism in the gene encoding the beta3 subunit of heterotrimeric G proteins is associated with enhanced activation of pertussis toxin (PTX)-sensitive G proteins. We investigated responses of human platelets upon stimulation with epinephrine, which activates PTX-sensitive G proteins, and with agonists which activate additionally, or exclusively PTX-insensitive pathways. Slopes and maximum of the secondary aggregation were significantly enhanced in platelets from 825T allele carriers after epinephrine, and after combined epinephrine/ADP. This effect was more pronounced after inhibition of the cyclooxygenase-2 pathway by acetylsalicylic acid. This phenomenon appeared independent of platelet secretion, or inhibition of the adenylyl cyclase.

[Electromechanically controlled versus roengenologically guided percutaneous transluminal laser myocardial revascularization]

Transmyocardial laser revascularization is a modern therapeutic concept for patients with end-stage coronary artery disease not eligible for bypass surgery, percutaneous coronary interventions or heart transplantation. Although the principal idea of creating additional myocardial perfusion from the cavum of the left ventricle was derived from observations in reptile hearts, histological investigations suggest that channel patency is not the underlying mechanism for improved clinical symptoms. Sympathetic denervation and angioneogenesis may be additional explanations for improvement of angina and stress tolerance. The first experiences with transmyocardial laser revascularization were made using a surgical approach. Two randomized multicenter trials could show a significant improvement in angina and stress tolerance 12 months after creating channels using laser technique. While these results were obtained by performing thoracotomy, catheter-based systems have been designed for a less invasive approach of this technique. A further advantage of these new systems is that regions like the septum can be treated which are not eligible for a surgical approach. Using percutaneous transluminal catheter-based systems channels of up to 6 mm length can be created. Beside the fluoroscopic guided creation of myocardial channels a new mapping system has been applied using electromechanical features of viable myocardial tissue. This system is based on the observation that endocardial electrograms recorded from an infarcted area are characterized by very low amplitude and fractionated morphology. This system allows online mapping of viable myocardium and provides spatial, electrical, and mechanical information of the myocardium. This method of electromechanical mapping highly correlates with results obtained from myocardial perfusion scans. Recent preliminary clinical trials demonstrated that catheter-based creation of myocardial channels is a feasible and successful alternative to the surgical laser revascularization. Also with this approach a significant improvement in angina and stress tolerance can be achieved. The results of the PACIFIC study, the first randomized multicenter study using percutaneous transluminal laser revascularization, demonstrates that after 3 and 6 months more than half of the patients presented improved angina of at least 1 Canadian-Cardiovascular-Society class. Whether electromechanical guided myocardial laser revascularization is more efficient than fluoroscopic guided has not been proven yet. Further studies will have to evaluate this issue.

Corrected coronary flow velocity reserve: a new concept for assessing coronary perfusion

OBJECTIVES

In order to limit the variability of coronary flow velocity reserve (CFVR), we analyzed which factors independently affect CFVR and established a new parameter integrating these factors.

BACKGROUND

Coronary flow velocity reserve (CFVR) is a frequently used parameter for evaluating the physiological significance of epicardial stenosis and microvascular function. Since CFVR measurements are done in substantially different hemodynamic and clinical situations, interpretation of CFVR requires correction for major influencing factors.

METHODS

In 141 patients with angina-like symptoms and angiographically unobstructed coronary arteries, intracoronary Doppler measurements were performed in at least two coronary vessels. Coronary flow velocity reserve was calculated as the ratio of hyperemic average peak velocity (hAPV), after intracoronary bolus of adenosine, to baseline average peak velocity (bAPV).

RESULTS

Analysis of covariance revealed that only bAPV (p < 0.0001) and age (p < 0.0001) were independent factors influencing CFVR. Based on a regression model for estimation of predicted CFVR values, individual CFVR values (CFVRind) obtained at different bAPV and age were transformed in corrected CFVR values (CFVRcorr) by relating them to a mean bAPV of 15 cm/s and a mean age of 55 years. The transformation from CFVRind into CFVRcorr for the left anterior descending artery can be done by using the following equation: CFVRcorr = 2.85*CFVR(ind)*10(0.48*log(bAPV)+(0.0025*age)-1.16). When applying this new parameter to conditions assumed to cause microvascular dysfunction, analysis showed that only patients with diabetes showed a significant decrease of traditional CFVR and CFVRcorr, whereas a history of hypertension and current smoking habit had no influence on CFVRcorr.

CONCLUSIONS

The concept of CFVRcorr standardizes CFVR for bAPV and age as the major physiological determinants. Especially in patients with microvascular dysfunction, this approach may help to discriminate between conditions directly affecting vasodilator reserve and conditions primarily affecting bAPV.

Early clinical experience with the implantation of a novel synthetic coronary stent graft

Coating stents with autologous venous grafts has been suggested to prevent problems associated with conventional stenting, but the need for surgical vessel harvest hampered broad application. A novel synthetic coronary stent graft (CSG) overcomes this limitation by a synthetic membrane, fixed between two thin metallic stents. We successfully implanted 21 CSGs in 18 patients for treatment of acute coronary rupture, thrombus-containing lesions, and lesions with plaque rupture or adjacent pseudoaneurysm. Substantial residual angiographic diameter stenoses were seen in seven CSGs (25% +/- 10% vs. 8% +/- 6%; P < 0.01), which were implanted with relatively small balloon catheters (balloon-to-artery ratio 1.00 +/- 0.09 vs. 1.24 +/- 0.18; P = 0.01) and required postdilatation. Overall, the largest balloon catheter applied measured 4.0 +/- 0.7 mm (balloon-to-artery ratio 1.21 +/- 0.20) and the inflation pressure was 16 +/- 3 atm. Final intravascular ultrasound imaging demonstrated adequate and symmetrical expansion of the CSG (> or = 85% +/- 15% of the reference lumen). Elective implantation was associated with two small non-Q-wave myocardial infarctions, resulting from unavoidable occlusions of side branches. Thus, implantation of CSG is feasible and safe. Adequate expansion can be achieved by the use of relatively large low-compliant balloon catheters inflated with high pressure.

[Management of coronary perforation after percutaneous balloon angioplasty with a new membrane stent]

A 59 year old patient underwent percutaneous transluminal coronary angioplasty of a de novo stenosis of the proximal right coronary artery. Vessel perforation occurred after balloon angioplasty and was successfully treated by implantation of a new stent graft, which completely covered the perforation without residual leakage. Emergency coronary surgery could, thus, be avoided.

Venous port systems in the field of gynaecological oncology

In the field of gynaecological oncology, which is characterised by the frequent application of cytotoxic drugs strongly necrotising to tissue, fully implantable venous port systems are of particular relevance. Frequent and serious complications such as infection, thrombosis, obstruction, leakage, or paravasation detract considerably, however, from the advantages otherwise deriving from a safe and reliable means of accessing a patient's venous system. Most complications are caused by the inexpert handling of these fully implantable catheters and should, therefore, be avoidable. In many cases, it will be possible after efficient diagnosis to solve the complication and keep the port functioning. On the basis of 8 actual cases typical and frequent complications observed in connection with port systems are described, together with preventive measures, diagnosis and therapy.

Complications in connection with venous port systems: prevention and therapy

Post-operative difficulties apart, venous thrombosis, extravasation and dislocation, obstruction, catheter leakage and local and systemic infections are the typical complications associated with venous port systems. Such complications considerably reduce the benefits otherwise accruing from a reliable access to the venous system of patients with malignant tumours. The vast majority of such disadvantages are attributable to the inexpert handling of ports and, therefore, should be avoidable. This applies to such areas as selecting the right port system, the proper installation of the port chamber and catheter and also to efficient handling and maintenance by trained staff. In may cases it will be possible, with the help of a specific diagnostic investigation, to identify and correct a fault and this ensure that the system installed continues to function. Typical and frequent complications observed (with specific examples) in connection with port systems are described together with preventative measures, diagnosis and therapy.

Analysis of vessel wall morphology, blood flow velocity, and the hemostatic system in a patient with a large intracoronary thrombus

A patient with AMI caused by a large thrombus in the proximal LAD was successfully treated with PTCA and an intracoronary lysis combined with the platelet-receptor antagonist c7E3. Analysis of cellular hemostasis after 1 and 6 months revealed a sustained platelet activation despite combined anti-platelet therapy with ASA and ticlopidine. A progredient slow-flow phenomenon appeared during control angiographies, confirmed by intracoronary Doppler examination.

[Treatment of a large intracoronary thrombus with urokinase and a chimeric monoclonal platelet aggregation inhibitor]

HISTORY AND CLINICAL FINDINGS

7 days after an operation for intervertebral disc prolapse a 43-year-old man was referred with the clinical and ECG signs of an acute posterior wall myocardial infarction.

INVESTIGATIONS

Creatine kinase (CK) activity was raised to 204 U/I (myocardial-specific isoenzyme CKMB of 23.6 U/I, 11.6% of total) and glutamic-oxalate transferase (GOT) activity to 37 U/I. Emergency cardiac catheterisation, performed 4 hours after renewed onset of precordial pain showed no abnormal findings in the right coronary artery, despite the ECG signs, but a definite filling defect in the anterior interventricular branch, which on intravascular ultrasound was an echo-dense noncalcified structure.

TREATMENT AND COURSE

After percutaneous transluminal coronary angioplasty in the area of the obstructing structure a free-floating mass was identified in the proximal part of the anterior interventricular branch, most likely a thrombus. Intercoronary thrombolysis was therefore undertaken with urokinase (bolus of 1 mill. IU) together with the chimeric monoclonal antibody c7E3, which inhibits platelet aggregation by blocking the platelet glycoprotein surface receptor IIb/IIIa. Coronary angiography 12 hours later revealed almost complete dissolution of the previously obstructing mass.

CONCLUSION

Combining the platelet aggregation inhibitor c7E3 with a thrombolytic agent is an alternative treatment to the current management of intracoronary thrombi. Intravascular ultrasound is a suitable method for demonstrating angiographically inconspicuous or unclear but pathogenetically significant vessel changes.

[Acute type A dissection of the ascending aorta after aortocoronary bypass operation]

A 63-year-old man with a history of hypertension and coronary artery bypass grafting (1 year ago) was admitted with acute onset severe chest pain suggesting bypass dysfunction. Biplane cineangiography revealed acute aortic dissection Stanford Type A without involvement of the aortic valve, the coronary arteries or the proximal anastomoses of the two venous bypass grafts, one of which was occluded. Urgent repair of the aorta by a prosthesis and reinsertion of the patent venous graft in the innominate artery by interposition of saphenous vein was performed without complications. Sixteen months later on routine follow-up a pseudoaneurysm of the ascending aorta surrounding the aortic prosthesis was discovered by transesophageal echocardiographic examination. Reoperation was performed with prosthetic replacement of the ascending aorta. The operative course and further follow-up of now 1.5 years were uneventful.

[Findings in 100 patients with idiopathic increase in serum creatine kinase activity]

BACKGROUND

In outpatient clinics for neuromuscular diseases sometimes patients are presented because of an raised activity of the serum creatine kinase (CK) activity, accidentally detected. The purpose of this study was to investigate, how many patients with an unexplained hyperCKemia really suffer from a neuromuscular disease, and to present an adequate procedure for evaluating pathological CK activities.

PATIENTS AND METHODS

In this retrospective study, clinical, electromyographic and myopathological findings of 100 consecutive patients (38 women and 62 men, aged 19 to 78 years) with such an abnormality of unknown origin are presented.

RESULTS

Only 41 patients really had no muscular troubles and no signs of neuromuscular disorders at physical examination. The CK of 12 patients turned to normal at follow-up examination. In 4 patients a so-called makro-CK was found. In 50 patients, in-depth examinations including a muscle biopsy were performed. In 10 patients, the increased CK-activity could be attributed to a complication of an already known basic disease, e.g., by confirming a myositis in case of proven connective tissue disease. In 14 patients an independent muscle disease was proven: 3 degenerative, 5 metabolic or mitochondrial as well as 4-inflammatory myopathies. In 2 patients, a secondary myopathy in polyneuropathy was suspected to be the etiology of the increased CK activity. In 9 patients, well treatable disorders were discovered. In 34 patients, no muscle biopsy was performed and follow-up examinations were recommended. The ratio of the clarified diagnoses did not depend on the level of the CK activity.

CONCLUSION

Every hyperCKemia indicates a thorough internal and neurological examination independently from the level of the enzyme activity. A scheme for examination in case of abnormal CK activity is proposed.

[Left ventricular dimensions and functions in the acute and chronic phase after myocardial infarct--comparison of cine-magnetic resonance tomography, angiocardiography, 2D-echocardiography and technetium ventricular scintigraphy]

To study left ventricular morphological and functional changes in the first six months after acute myocardial infarction, 37 patients (28 male, 9 female, age 42-78 years) underwent cardiac Cine-MRT 1 week, 4 weeks and 6 months after their first myocardial infarction. MR-tomograms were oriented to left ventricular true long and short axis. For comparison, contrast angiocardiographic, radionuclide and echocardiographic left ventricular studies were performed. LV-volume was calculated with the Simpson method for long axis images and by summation of slices for short axis images. Cine MRT results showed the following correlation to angiocardiography: in long axis r = 0.945 for LVEDVI, r = 0.958 for LVESVI, r = 0.869 for LVEF and r = 0.885 for cardiac index; in short axis r = 0.956 for LVEDVI, r = 0.965 for LVESVI, r = 0.917 for LVEF and r = 0.844 for cardiac index. For LVEF correlation to technetium radionuclide ventriculography was r = 0.760 in long and r = 0.861 in short axis. Correlation between Cine-MRT and echocardiography was poor as a consequence of the great variance of echogenity in the study patients. We conclude that Cine-MRT is an excellent method for morphological and functional left ventricular investigation, still limited in clinical praxis by costs and duration. As known from earlier investigations the development of left ventricular dilatation and functional disturbance was influenced by the size and location of the infarction with infarct size being the primary factor in the early and infarct location in the late post-infarction period. Outcome was worst following large anterior infarction.

ACE inhibition facilitates sodium and water excretion during PEEP in conscious volume-expanded dogs

Increased activity of the renin-angiotensin system may be involved in sodium and water retention during controlled mechanical ventilation (CMV) with positive end-expiratory pressure (PEEP). We therefore evaluated renal, hemodynamic, and hormonal effects of an acute angiotensin-converting enzyme inhibition (ACEI) during PEEP and extracellular volume expansion in five trained chronically tracheotomized dogs. Three protocols were performed: control, 4 h spontaneous breathing with continuous positive mean airway pressure (Paw) of 4 cmH2O (CPAP 4); CMV 20, CPAP for 1st h, CMV with 20 cmH2O Paw for 2 h (2nd and 3rd h), and 1 h of CPAP (4th h); and CMV20-ACEI, ACEI (Ramipril, 2 mg/kg body wt) followed by the same protocol as in CMV 20. During control, sodium excretion (UNaV) and urine volume (V) increased continuously to 56.2 +/- 2.7 (SE) mumol.min-1.kg body wt-1 and 482 +/- 23 microliters.min-1.kg body wt-1, respectively. UNaV and V increased less during PEEP in CMV 20 and CMV 20-ACEI. However, significantly more sodium and water were retained in CMV 20 than in CMV 20-ACEI (2.3 +/- 0.3 vs. 1.0 +/- 0.3 mmol/kg body wt, and 20 +/- 3 vs. 11 +/- 2 ml/kg body wt) because of a decrease of glomerular filtration rate and fractional UNaV in CMV 20. Heart rate did not change in control, CMV 20, or CMV 20-ACEI. Mean arterial pressure increased during control by 13 mmHg, did not change during CMV 20, and was decreased by 7 mmHg in CMV 20-ACEI.(ABSTRACT TRUNCATED AT 250 WORDS)

Vasculogenesis in the early quail blastodisc as studied with a monoclonal antibody recognizing endothelial cells

QH1, a monoclonal antibody that recognizes quail endothelial and haemopoietic cells, was applied to quail blastodiscs in toto, in order to analyse by immunofluorescence the emergence of the vascular tree. The first endothelial cells were detected in the area opaca at the headfold stage and in the area pellucida at the 1-somite stage. Single cells then interconnected progressively, especially in the anterior intestinal portal and along the somites building up the linings of the heart and dorsal aortas. This study demonstrates that endothelial cells differentiate as single entities 4 h earlier in development than hitherto detected and that the vascular network forms secondarily. The horseshoe shape of the extraembryonic area vasculosa is also a secondary acquisition. A nonvascularized area persists until later (at least the 14-somite stage) in the region of the regressing primitive streak.

[Improved access to the superficial femoral artery in PTA using a Tuohy cannula]

Description of a new needle well suited for problem cases in percutaneous transluminal angioplasty of the superficial femoral artery. This needle facilitates probing of the vessel in antegrade puncture and makes sliding off into the deep femoral artery less likely.