Mustafa Özcan

Effect of Valsalva maneuver on surface electrocardiographic P-wave dispersion in paroxysmal atrial fibrillation

The purpose of this study was to investigate the effect of the Valsalva maneuver on P-wave durations and dispersion. After the Valsalva maneuver, we found that maximum P-wave duration increased, minimum P-wave duration decreased, and P-wave dispersion increased in controls, whereas the opposite was true for unselected patients with paroxysmal AF. It was concluded that patients with paroxysmal AF performing the Valsalva maneuver normalized their P-wave dispersion, thereby correcting the inhomogeneous intra-atrial conduction.

The role of aspirin resistance on outcome in patients with acute coronary syndrome and the effect of clopidogrel therapy in the prevention of major cardiovascular events.

AbstractBackground: Aspirin resistance may increase up to more then threefold the risk of major cardiovascular events (MACE) in patients with stable coronary artery disease. Aim:The aim of our study was to determine; the prevalence of aspirin resistance in patients with acute coronary syndromes, the role of aspirin resistance on outcome in the follow-up and the effect of clopidogrel therapy in the prevention of MACE in aspirin resistant subjects. Material and methods: We detected the prevelance of aspirin resistance in 105 patients with acute coronary syndrome. Platelet functions were analyzed in Platelet Function Analyzer (PFA)-100 (Dade Behring, Germany) with collagen and/or epinephrine (Col/Epi) and collagen and/or ADP (Col/ADP) cartridges. Primary end points of the study were myocardial infarction, unstable angina, cardiac death. Results: 19% (n = 20) of patients were aspirin resistant by PFA-100. In the follow-up, MACE occured in 9 patients (45%) with aspirin resistance and in 10 patients (11.7%) with aspirin sensitive platelet aggregation (p = 0.001). Multivariate analysis showed that aspirin resistance was an independant predictor of MACE. The prevalence of MACE in patients who were on clopidogrel treatment for 12 months were lower compared to those who were on a clopidogrel treatment for the first six months (p = 0.040). Conclusions: We determined that the MACE risk in patients with acute coronary syndromes having detected aspirin resistance, was higher at statistically significant levels compared to patients having aspirin sensitive platelet aggregation. Our results showed that aspirin resistance, was an independant predictor of MACE in patients with acute coronary syndrome.

Heart rate variability in diabetes patients.

Diabetes mellitus can cause cardiovascular autonomic neuropathy and is associated with increased cardiovascular deaths. We investigated cardiovascular autonomic neuropathy in diabetics and healthy controls by analysis of heart rate variability. Thirty-one diabetics and 30 age- and sex-matched controls were included. In the time domain we measured the mean R-R interval (NN), the standard deviation of the R-R interval index (SDNN), the standard deviation of the 5-min R - R interval mean (SDANN), the root mean square of successive R - R interval differences (RMSSD) and the percentage of beats with a consecutive R - R interval difference > 50 ms (pNN50). In the frequency domain we measured high-frequency power (HF), low-frequency power (LF) and the LF/HF ratio. Diabetes patients had lower values for time-domain and frequency-domain parameters than controls. Most heart rate variability parameters were lower in diabetes patients with chronic complications than in those without chronic complications.

Carcass measurements and meat quality of Turkish Merino, Ramlic, Kivircik, Chios and Imroz lambs raised under an intensive production system

Effect of breed on carcass measurements and meat quality characteristics were investigated by using 46 lambs from Turkish Merino, Ramlic, Kivircik, Chios and Imroz breeds. Chios and Imroz carcasses had smaller values for carcass quality characteristics. Breed had no significant effect on pH at 45min and 24h post-mortem, water holding capacity and cooking loss. Kivircik and Imroz lambs had lower Warner Bratzler shear force values than those of Ramlic and Turkish Merino lambs (P<0.01). Meat samples from Kivircik lambs had the highest redness value. Differences among breeds for sensory characteristics, except tenderness were not significant. Tenderness scores given to meat samples of Kivircik lambs were significantly higher (P<0.01) than those of Turkish Merino, Ramlic and Imroz lambs. Indigenous Kivircik breed, which had high carcass quality as those of improved breeds, might be considered for production of better quality meat in Marmara Region of Turkey.

Clinical relevance of aspirin resistance in patients with stable coronary artery disease: a prospective follow-up study (PROSPECTAR).

Aspirin resistance may increase the risk of major adverse cardiac events (MACE) more than threefold in patients with stable coronary artery disease (CAD). This study aimed to determine the prevalence of aspirin resistance in patients with stable CAD, the role of aspirin resistance on outcome in the follow-up, and the effect of clopidogrel therapy in MACE prevention in aspirin-resistant individuals. We detected the prevalence of aspirin resistance in 234 patients with stable CAD. Platelet function was determined by PFA-100 with collagen and/or epinephrine and collagen and/or ADP cartridges. The mean follow-up time was 20.6 ± 6.9 months. The primary endpoints of the study were occurrence of myocardial infarction, unstable angina, stroke and cardiac death. Of patients, 22.2% (n = 52) were aspirin resistant by PFA-100. During follow-up, MACE occurred in eight patients (15.4%) with aspirin resistance and in 20 patients (11.0%) with aspirin-sensitive platelet aggregation (P = 0.269). MACE increased in aspirin-resistant patients after termination of clopidogrel therapy. Eleven patients experienced MACE after cessation of clopidogrel therapy (P < 0.001). The MACE risk in patients with stable CAD having detected aspirin resistance was similar compared with patients having aspirin-sensitive platelet aggregation by PFA-100. The MACE prevalence increased during follow-up, however, just after cessation of clopidogrel therapy.

Surgical Treatment of Cardiac Echinococcosis: Report of Eight Cases

Abstract Cardiac involvement of hydatid disease is uncommon, and establishing a diagnosis is difficult because the presenting symptoms are variable. Between 1985 and 1997, eight patients ranging in age from 8 to 56 years underwent surgical excision of cardiac hydatid cysts, located in the interventricular septum in two, the right atrium in one, and the intrapericardium in five. There was one hospital death due to septic shock, but the other seven patients recovered uneventfully.

Autonomic dysfunction in vitamin B12 deficiency: a heart rate variability study.

This study was arranged to examine whether vitamin B12 deficiency may cause autonomic dysfunction. Time-domain and long-term frequency-domain heart rate variability parameters from 12 patients with pernicious anemia were compared to 12 age and sex matched controls. In B12 deficient patient group time-domain parameters; SDNN (100.4 +/- 37.86 vs. 131.91 +/- 26.94, P = 0.05), SDANN (87.00 +/- 37.77 vs. 118.83 +/- 26.22, P = 0.05) SD (39.41 +/- 13.32 vs. 53.41 +/- 15.39, P = 0.0221), rMSSD (21.41 +/- 10.00 vs. 28.5 +/- 8.42, P = 0.046) were significantly lower when compared to controls. Difference in pNN50 between groups were not statistically significant. In B12 deficient patients frequency-domain parameters; total power (23.08 +/- 9.89 vs. 34.75 +/- 9.56, P = 0.0078), low frequency power (13.5 +/- 6.57 vs. 22.75 +/- 7.25, P = 0.0069) and high frequency power (7.58 +/- 4.25 vs. 11.58 +/- 3.80, P = 0.0175) were significantly lower when compared to controls. It was concluded that B12 deficiency may cause autonomic dysfunction.

Carcass measurements and meat quality characteristics of dairy suckling kids compared to an indigenous genotype.

Effects of genotype on carcass measurements and meat quality were investigated by using 24 suckling kids from Turkish Saanen, Gokceada and Maltese breeds. Carcass quality characteristics of indigenous kids (Gokceada) were lower than those of dairy type (Turkish Saanen and Maltese) kids. Breed effect on ultimate meat pH, cooking loss, drip loss and Warner Bratzler shear force values were not significant. Meat samples from Turkish Saanen kids had higher redness (at 0, 1 and 24h) and yellowness (at 24h) values than Gokceada kids (P<0.05). Breed had no significant effect on sensory characteristics except flavour intensity. Flavour intensity scores given to meat samples of Maltese kids were higher than those of Turkish Saanen and Gokceada kids (P<0.01). In conclusion, dairy type breeds should be considered for meat production as well, with meat from Maltese kids potentially offering better colour and flavour intensity than that of Turkish Saanen kids.

Effects of crossbreeding indigenous Hair Goat with Saanen on carcass measurements and meat quality of kids under an intensive production system.

The aim of study was to investigate the effect of genotype on carcass measurements and meat quality characteristics of purebred Hair Goat, Saanen x Hair Goat (F(1) and B(1)) kids under an intensive production system. In total, 24 kids were slaughtered at the age of approximately 133 days. Kids were fattened for 56 days immediately after weaning. Hot carcass weights were 6.78, 7.61 and 7.02 kg and dressing percentages were 49.71, 49.27 and 48.78%, respectively (P > 0.05). Differences between genotypes for carcass measurements and indexes were not significant. Effect of genotype on pH measurements, drip loss, water holding capacity, cooking loss and Warner Bratzler shear force values were not significant. Meat lightness values at 0 h, 1 h and 1 day after cutting were higher in crossbred kids than Hair Goat kids (P < 0.05). Redness value was significantly higher in meat samples of Hair goat kids at 0 h, 1 h and 1 day measurements (P < 0.05). Kid genotype had no significant effect on meat sensory characteristics, except tenderness. Panelists gave lower scores for meat tenderness to F(1) and B(1) crosses compared to purebred Hair Goat kids. In conclusion, higher meat lightness values of crossbred kids, at particularly B(1) level, might have a positive effect on the consumer choices.

The role of HLA molecules in susceptibility to chronic rheumatic heart disease

Only a small fraction of the streptococcal pharyngitis progress to rheumatic carditis, which implies that environmental, host and microbial factors interact to cause an aberrant immune response against the antigens of the microorganism that cross‐react with cardiac tissues. Although there are numerous studies and a general consensus on the relation between human leucocyte antigen (HLA) class II antigens and rheumatic heart disease (RHD), the details and the culprit antigens are still controversial. The study was undertaken to examine 100 patients with chronic RHD and 100 controls for HLA class I and class II antigens for differences in prevalence. All samples were typed at the HLA‐DRB1/3/4/5 and DQB1 loci by the sequence‐specific primer (PCR‐SSP) method at low resolution. For HLA class I antigens, HLA‐B13 frequency was marginally increased in patients with RHD compared to controls without reaching statistical significance. For class II antigens, RHD patients had higher frequencies for HLA‐DRB1*01 (RHD 24%, controls 10%), DRB1*04 (RHD 35%, controls 26%), DRB1*07 (RHD 18%, controls 11%) and HLA‐DQB1*02 (RHD 32%, controls 17%) without reaching statistical significance, and significantly lower frequencies for DRB1*13 (Pc < 0.003, OR: 5.69), DRB5* (Pc < 0.003, OR: 33) and DRB3* (Pc = 0.03, OR: 2.66) compared to controls. It was concluded that host, microbial and environmental factors collude to create acute rheumatic fever (RF) and chronic rheumatic valve disease. The HLA‐DRB1*13, DRB5* and DRB3* were protective against the development of rheumatic valve damage.