Gene polymorphisms of renin angiotensin system and serotonin transporter gene in patients with vasovagal syncope.

UNLABELLED: Objective of this study was to compare the distribution frequencies of gene polymorphisms of renin-angiotensin and serotonin system in patients with positive and negative head- up tilt test (HUT). METHODS: DNA from 191 patients (mean age 44+ 18 years, 61 men) was collected. HUT was positive in 117 and negative in 74 patients. Following gene polymorphisms were determined by the PCR method: ACE insertion/deletion (I/D ACE), angiotensinogen (AGT) (M 235), angiotensin II receptor (ATR1) (A 1166C) and serotonin transporter (SERT) polymorphism (5HTTLPR). RESULTS: No significant differences in the distribution of gene polymorphisms between syncopal patients with positive and negative HUT were dectected. Distribution of polymorphisms included: I/D ACE: II 19 vs 20%, ID 55 vs 52%, DD 26 vs 28%. Angiotensinogen gene polymorphism MM 27% vs 30%, MT 48% vs 46%, TT 25% vs 24%. ATR1 polymorphism AA 44 vs 32%, AC50 vs 60%, CC 6 vs 8%, 5HTTLPR serotonin transporter gene polymorphism LL 42 vs 43%, SL 41 vs 39%, SS 17 vs 18%. CONCLUSIONS: An association between polymorphisms of ACE, AGT, ATR1 and SERT gene, and predisposition to VVS was not proven by the present study (Tab. 2, Ref. 22). Full Text (Free, PDF) www.bmj.sk.

Relation of various degrees of body mass index to systolic and diastolic dysfunctions.

OBJECTIVES: This study was designed to identify any associations between left ventricular function and obesity using clinical two-dimensional echocardiographic and Doppler studies. METHODS: We retrospectively evaluated 260 consecutive clinical echocardiographic findings. Key echocardiographic variables of systolic and diastolic function were related to various degrees of body mass index. RESULTS: In multiple regression analysis in the whole group of patients there was significant relation of body mass index to left ventricular mass and its indexed value (p < 0.0001). Multiple regression analyses in subgroups of patients according to systolic and diastolic function or dysfunction revealed similarly the strongest association of body mass index to mainly left ventricular mass. In subgroups of patients classified on the basis of their body mass indices significant differences were found also in case of left ventricular mass as well as left atrial volume (p = 0.0001, and p = 0.003, respectively). There was no association between body mass index and systolic or diastolic dysfunction. CONCLUSION: We found strong association between obesity and left ventricular mass. Obesity was not related to systolic and diastolic function or dysfunction.

Diagnostic yield of adenosine and nitroglycerine stimulated tilt test in patients with unexplained syncope.

OBJECTIVES: We aimed to compare diagnostic yield of adenosine tilt test (A-HUT) with nitroglycerine tilt test (NTG-HUT) in patients with unexplained syncope and to assess the use of adenosine tilt test as an alternative to routine tilt testing. BACKGROUND: Adenosine could provoke a vasovagal response in susceptible patients. Adenosine stimulated tilt testing is less time consuming than conventional tilt testing. METHODS: Forty-one consecutive patients with unexplained syncope were tested (29 females /12 males; mean age 44 +/- 20 years). As a part of standard diagnostic testing they undewent both adenosine and nitroglycerin stimulated tilt testing in random fashion. RESULTS: NTG-HUT was positive in 28 patients (68%). Six patients (14.6 %) developed a vasovagal response after adenosine stimulated head-up tilt test (A-HUT). All patiens with positive A-HUT showed also the positivity of NTG-HUT. No patient from with negative NTG-HUT developed a vasovagal response after adenosine induction. The diagnostic yield of NTG-HUT was significantly higher than yield of A-HUT (p < 0.001). The diagnostic yield of A-HUT was significantly affected by age. Subjects with a positive adenosine tilt test were younger than those with a negative tilt (29 +/- 10 vs. 46 +/- 20 years, p = 0.016). Five of six positive patients were <30 years of age. Diagnostic yield in those patients was 31%, whereas in patients >30 years of age was significantly lower (4%, p = 0.007). CONCLUSION: Diagnostic yield of the adenosine stimulated tilt testing is significantly lower than diagnostic yield of nitroglycerine stimulated tilt testing. Given the very short time needed for performing adenosine stimulated HUT, it may be useful in patiens <30 years of age. In this group of patiens positive adenosine-stimulated HUT may obviate need for the time consuming nitroglycerine-stimulated HUT (Tab. 1, Fig. 3, Ref. 17).

[Diagnostic benefit of the use of implanted loop recorder (Reveal Plus) for patients with syncope with unclear aetiology]. / Diagnostický prínos pouzitia implantovaného sluckového rekordéra (Reveal Plus) u pacientov so synkopou nejasnej etiológie.

UNLABELLED: The objective of the study was to evaluate the diagnostic yield of a loop recorder (Reveal Plus, Medtronic) in the diagnosis of syncope conditions whose aetiology remains unclear despite the performance of a full diagnostic procedure. PATIENTS AND METHOD: Loop recorders were implanted in 25 patients with recurrent syncope (9 men, 16 women, average age 59 +/- 14 years), who reported 4 +/- 2.7 episodes of syncope (2-10 episodes). A complete diagnostic algorithm was performed for all patients before implantation including the head-up tilt test, an invasive electrophysiological examination and a neurological examination. The aetiology of the syncope was not established by these examinations. RESULTS: During an average monitoring period of 13 +/- 8 months (1-24 months) 10 patients experiences recidivating syncope, 7 patients experienced pre-syncope and 1 patient experienced palpitations. 7 were asymptomatic during monitoring. Symptomatic arrhythmia was detected in 10 patients (40%). The most frequent finding was bradyarrhythmia (6 patients--sinus arrest in 3 patients, serious bradycardia in 2 patients, AV block in 1 patient). Tachyarrhythmia was the cause of symptoms in 4 patients (supraventricular tachycardia in 3 patients, ventricular bigeminy in 1 patient). In the case of 5 patients (20%) syncope (pre-syncope) took place in the absence of a serious arrhythmia and was classified as vasovagal syncope. CONCLUSION: The implantable loop recorder established a diagnosis in 15 of 25 patients (60%) with syncope that was not diagnosed by conventional tests and it is a highly beneficial method for diagnosing syncope.

Role of the peripheral serotoninergic system in the pathogenesis of vasovagal syncope.

OBJECTIVE: To evaluate the role of peripheral serotoninergic system in the pathogenesis of vasovagal syncope. BACKGROUND: Increased central serotoninergic activity was suggested to play a role in sudden inhibition of sympathetic activity responsible for the genesis of vasovagal syncope. There is good correlation between the central serotoninergic activity and the plasma levels of serotonine. METHODS: In twenty-two patients (mean age 48 +/- 19 years, 10 men, 12 women) with suspected vasovagal syncope head-up tilt test (HUT) was performed. Passive HUT (60 degrees, 20 minutes) was followed, if negative, by nitroglycerine stimulated HUT (400 microg sublingually, 15 minutes). Blood samples were obtained at baseline (in supine position), in 5 minute, 15 minute of HUT and finally at syncope or end of the test. Plasma levels of serotonine were measured by enzyme-immunoassay (EIA) method. RESULTS: HUT was positive in fifteen patients and negative in seven patients. In all HUT positive patients syncope developed after nitroglycerine stimulation. Mean duration of nitroglycerine phase was 4.8 +/- 1.2 min. In 5 min of HUT serotonine level was significantly lower in HUT positive patients HUT (102.40 +/- 43.11 vs 160.85 +/- 43.71 ng/ml, p = 0.01). At the time of syncope no significant differences were observed between HUT positive and HUT negative patients (184.26 +/- 118.72 vs 196.57 +/- 88.91 ng/ml, p = 0.40). CONCLUSION: In patients with vasovagal syncope lower level of plasma serotonine were observed during early HUT when compared to controls. No differences in serotonin activity were observed at the time of syncope (Tab. 1, Fig. 1, Ref. 24).