Thin-cap fibroatheroma and increased coronary intima-media thickness are associated with an altered balance of arginine metabolites.

INTRODUCTION: Arginase inhibition increases plasma citrulline and citrulline / ornithine (C/O) ratio, and reduces plasma ornithine and ornithine / arginine (O/A) ratio in an animal model of myocardial infarction (MI). OBJECTIVES: We hypothesized that the presence of thin­cap fibroatheroma (TCFA) in the culprit lesion and increased non­culprit intima­media thickness of an infarct­related artery (IRA) are associated with an altered balance of arginine metabolites. PATIENTS AND METHODS: Arginine and its metabolites were measured using liquid chromatography and tandem mass spectrometry in 100 consecutive MI patients upon admission and at 6­month follow­up. TCFA and adjacent to culprit lesion proximal and distal 10­mm segments were assessed with optical coherence tomography in the acute phase. Twenty five patients without coronary lesions on angiography served as controls. RESULTS: The C/O ratio increased 5.33 times (P <0.001), while the O/A ratio decreased 2.53 times (P <0.001) at the 6­month follow­up, as compared with the acute phase of MI. The patients with (n = 75) vs without (n = 25) TCFA had lower C/O ratio by 29% (P = 0.003), while the mean intima­media diameter of adjacent non­culprit region correlated with the follow­up O/A ratio (R = 0.337; P = 0.003). In a multivariable analysis, a higher acute phase C/O ratio was associated with a lower risk of TCFA presence (odds ratio, 0.978; 95% CI, 0.962-0.994; P = 0.006), whereas a higher follow­up O/A ratio correlated with larger intima­media diameter of the adjacent segments (ß coefficient, 0.227; 95% CI for ß coefficient, 0.045-0.409; P = 0.018). CONCLUSIONS: Enhanced arginase activity over nitric oxide synthase following ischemia was associated with the presence of TCFA in the culprit lesion, while a similar metabolic shift in the chronic phase correlated with a greater thickness of the intima­media in the adjacent non­culprit IRA segments.

Influence of the recurrent syncope episodes on neurocognitive functions in patients with vasovagal syncope.

The aim of study was to evaluate an influence of recurrent syncope episodes on the neurocognitive functions (NCF) in patients with suspected VVS. AIM: The aim of study was to evaluate an influence of recurrent syncope episodes on the neurocognitive functions (NCF) in patients with suspected VVS. MATERIALS AND METHODS: Study population: 24 pts. (16 women) aged 17-70 yrs (mean age 40 years), with suspected VVS, referred to HUTT (head-up tilt test). All pts. underwent initial evaluation regarding to the number and circumstances of the syncopal and/or presyncopal spells. All pts performed HUTT with Westminster protocol. Basing on the syncope history and HUTT results, two groups of pts were distinguished: gr. I - 18 pts with at least 2 syncopal spells and positive HUTT, and gr. II 6 pts with only presyncopal status without complete loss of consciousness and negative HUTT. All pts underwent the evaluation of NCF with computer-assisted Vienna Test System battery, consisted of the following tests: DAUF - evaluation of long-term selective attention and concentration; COG - assessment of attention and concentration; STROOP - registration of the color-word interference tendency, CORSI - estimation of visual short-term memory capacity and implicite visuo-spatial learning. Values of the measured parameters were compared between both groups of pts. RESULTS: Patients without syncope (gr. II) had higher number of correctly reproduced sequences (11,0 vs 8,38 p<0,01) and Reliable Spatial Span score (5,50 vs 4,46,p<0,02) in CORSI test, in relation to pts with syncope history (gr. I). This suggests possible influence of the recurrent syncope episodes on the short-term memory capacity in pts with VVS. There were no significant differences between groups, comparing results of the other tests. CONCLUSIONS: Repeated syncope episodes may lead to impairment of short-term memory capacity in patients with vasovagal syndrome. Syncope episodes may have potentially negative influence on neurocognitive functions in patients with vasovagal syndrome.

The effects of gender and test protocol on the results of head-up tilt test in patients with vasovagal syncope.

BACKGROUND: Head-up tilt testing (HUTT) is a well-established method for the diagnosis of reflex syncope. Some controversies exist whether gender and HUTT protocol influence HUTT results. AIM: To analyse the results of HUTT in patients with syncope in relation to their gender and used protocol of HUTT. METHODS: We retrospectively analysed data of 537 consecutive patients (313 women and 224 men), aged 13-79 years with history of neurally-mediated syncope referred to HUTT. The cardiogenic and neurological aetiology of syncope was excluded in all patients based on previous examination. In 375 patients standard HUTT (STD HUTT), according to the Westminster protocol, was used. In 257 patients in whom STD HUTT was negative, HUTT was continued with pharmacological provocation using isoproterenol intravenous infusion--114 patients (ISO HUTT) or sublingual nitroglycerin--143 patients (NTG HUTT). In the remaining 162 patients HUTT was performed according to the Italian protocol (ITL HUTT). The HUTT results were classified according to the VASIS scale. RESULTS: Female gender dominated, however, syncope was induced in a similar proportion of women and men (77.3 vs. 70.5%, NS). There were also no significant differences in the type of vasovagal response (VVR) to HUTT between women and men. Mixed type of VVR was the most frequent after isoproterenol provocation (ISO HUTT), whereas cardioinhibitory type of VVR was the most frequent after nitroglycerin provocation (NTG HUTT). CONCLUSIONS: There is no significant relationship between gender and the result of HUTT. The type of VVR is related to HUTT protocol--cardioinhibitory response is more frequent following nitroglycerin administration in comparison to standard protocol and HUTT with isoproterenol provocation.

Evaluation of sinus and atrioventricular nodes function in patients with vasovagal syncope.

AIM: Evaluation of sinus and atrioventricular nodes function as a potential factor responsible for prolonged bradycardia, asystole, or both in patients with cardioinhibitory and non-cardioinhibitory vasovagal syncope (VVS). The study included 258 patients (mean age = 47.7 +/- 17.2 years; range 18-62; 147 females) with a history of VVS. They were divided among four groups, according to results of head-up tilt test (HUTT). METHODS: All patients underwent standard HUTT, carotid sinus massage (CSM), and rapid transesophageal atrial pacing for evaluation of total sinus node recovery time (SNRT), and corrected sinus node recovery time (CNRT), resting and intrinsic heart rate (IHR), and Wenckebach point (WP). Values of SNRT > 1,500 ms, CNRT > 525 ms, WP < 130 bpm, and CSM-induced pause >3 seconds were considered abnormal. RESULTS: SNRT, CNRT, and WP before and after pharmacological blockade, resting heart rate, and IHR did not differ significantly among the study groups. The prevalence of mild sinus node dysfunction (SND), decreased value of WP, and cardioinhibitory carotid sinus hypersensitivity was similar among all study groups. CONCLUSIONS: The prevalence of mild SND, abnormal atrioventricular conduction, and carotid sinus hypersensitivity (CSH) was similar among patients with VVS regardless of the type of vasovagal reaction. SND and CSH do not seem to play an important role in the pathogenesis of cardioinhibitory vasovagal reaction.

[Clinical significance of exercise-induced ST-segment elevation in lead aVR and V1 in patients with chronic stable angina pectoris and strongly positive exercise test results]. / Znaczenie kliniczne wysilkowego uniesienia odcinka ST w odprowadzeniach aVR i V1 u chorych z przewlekla stabilna dusznica bolesna i wybitnie dodatnim elektrokardiograficznym testem wysilkowym.

Electrocardiographic abnormalities in lead aVR and V1 are rarely analyzed on exercise electrocardiograms. Clinical significance of exercise-induced ST-segment changes in lead aVR and V1 during strongly positive electrocardiographic exercise test (EET) in patients with chronic stable angina pectoris remains unclear. The aim of the study was to assess the value of lead aVR and V1 on the exercise electrocardiogram for the detection of left main coronary artery stenosis (LMCAS) and its equivalent (LMCASE) in patients with chronic stable angina pectoris and the strongly positive EET result. The study group consisted of 118 consecutive patients (mean age 58.8 +/- 9.5 years, range 38-77 years), including 30 (25.4%) women. Patients were divided into three groups. In group I, 31 patients with ST elevation in lead aVR and V1, in group II 66 patients with isolated ST elevation in lead aVR, and in group III 21 patients without ST elevation in lead aVR, induced with exercise, were included. Coronary arteriography results were compared among these groups. In patients with isolated exercise-induced ST elevation in lead aVR, the prevalence of LMCAS was five times more frequent than in patients without lead aVR ST elevation (25.8% vs 4.8% p<0.05). There were no differences in the prevalence of LMCASE and multi-vessel coronary disease in the studied groups. In patients with LMCAS significant ST elevation in lead aVR during strongly positive EET were observed (0.25 +/- 0,4 mm vs 1.43 +/- 0.6 mm p = 0.003), whereas there were no significant exercise-induced electrocardiographic changes in lead V1 (0.61 +/- 0.6 mm vs 0.77 +/- 0.6 mm p = 0.08). Sensitivity of isolated exercise-induced ST elevation in lead aVR in detection of LMCAS was 85.0%, specificity - 50.0%, positive predictive value - 25.8%, negative predictive value - 94.2%, and total accuracy - 55.9%. Exercise-induced ST elevation in lead aVR on the strongly positive exercise ECG may detect LMCAS in patients with chronic stable angina pectoris.