Biomedical subjects

D Zanna

Publications and source records attributed to D Zanna.

13 recordsLinked to original sources

PubMed2006

Coronary flow, VO2 peak and anaerobic threshold in patients with dilated cardiomyopathy.

BACKGROUND: Coronary flow is influenced by several determinants and may change according to external stimuli. In patients with dilated cardiomyopathy (DC), adaptive mechanisms could induce alterations in coronary flow, possibly related to oxygen consumption. METHODS: In 67 consecutive patients with DC (mean age 52.06+/-13.84, 52 male gender, left ventricle ejection fraction (LVEF) 29.49%+/-8.68) and normal coronary angiography findings, coronary flow in left anterior descending (LAD), right coronary artery (RC) and left circumflex (LCx) was reported as TIMI frame count (TFC). All patients underwent a cardiopulmonary test with VO2 peak and anaerobic threshold (AT) measurement, New York Heart Association (NYHA) class stratification, two-dimensional echocardiographic evaluation including LVEF and left ventricle end-diastolic diameter (LVEDD) assessment. All patients were receiving optimal medical treatment. RESULTS: In a multivariate analysis, a statistically significant correlation was found between VO2 peak and TFC (B 7.61, p<0.001, R2 0.61 for LAD; B 3.42, p<0.001, R2 0.33 for RC); an inverse correlation was found between AT and TFC (B -9.77, p<0.001, R2 0.61 for LAD; B -4.26, p<0.001, R2 0.33 for RC). CONCLUSIONS: Coronary flow is related to VO2 peak and AT in patients with DC, suggesting a "compensatory" mechanism.

Anaerobic Threshold↗

PubMed1998

Assessment of cardiac vagal activity in patients with hyperthyroidism.

Previous studies suggested that in patients with hyperthyroidism an autonomic imbalance and in particular a lower than normal vagal activity might be present. To verify this hypothesis we have evaluated the respiratory sinus arrhythmia (RSA, a measure of cardiac vagal activity) in ten hyperthyroid patients and in ten normal subjects. RSA was calculated from the power of the spectral component of the heart rate variability in high frequency band (HF-RR) during both spontaneous (supine and passive head-up tilt) and controlled breathing (supine). During controlled breathing the phase relation between heart rate and respiratory has been computed. The hyperthyroid patients showed a higher heart rate in all three conditions (P<0.001) and higher spontaneous respiratory rate in supine position (centered frequency of HF-RR: 0.342+/-0.015 vs 0.262+/-0.016 Hz; P<0.001). No difference was found in hyperthyroid patients compared to controls in terms of the HF-RR power in normalized units both during spontaneous breathing (supine, 43+/-8.3 vs 39.7+/-6.7%; tilt 18.8+/-5.9 vs 19.3 vs 4.1%; mean+/-SE) and controlled breathing (45.4+/-7.1 vs 48.9+/-6.9%). No difference was found also in terms of the phase relationship between the heart rate and the respiratory signals (77.5+/-32.3 vs 77.5+/-28.1, degrees). Hyperthyroid patients seem not to have an impaired cardiac vagal activity.

Adult↗

PubMed1997

[Lipids in enteral nutrition: does an optimal ratio between omega-6 and omega-3 exist?].

The ratio between PUFA omega-6 and omega-3 is 3:1 in the unweaned, 5:1 in the young man, 5-10:1 in the adult. The PUFA omega-6 prevail over omega-3 because of elongation and desaturation processes. Linoleic acid is the beginning of the omega-6 series, a-linolenic acid of the omega-3 series. Both acids give rise to PUFA which must be introduced with diet because the human race is not able to synthetize. They represent the 2-6% of total daily caloric intake and correspond about to 10 g every day according to LARN 1986-1987. During some diseases (after surgery, trauma, sepsis, etc.) their need increases until 25-50 g every day, so it is necessary a proper enteral nutrition (EN). For this reason the bromatological composition of diets for EN must respect the physiological ratio between omega-6 and omega-3 PUFA. The composition of 37 diets for EN was examined and it was found that 7 (18%) have a proper ratio between the two series of PUFA. Twenty-three (62%) do not signal any ratio, two have 6:1, two 4.5:1, in three the ratio is in favour of omega-3. Then the concentration of linoleic and alfa-linolenic acid was examined and it was found that 24 (64%) diets signal the concentration of linoleic acid, 10 (27%) of both acids, two have no data about and only one diet reports the concentration of alfa-linolenic acid. A more exact formulation of PUFA into the composition of EN diets is suggested because PUFA are now recognized to play an important role in the fields of inflammation and immunity.

English Abstract↗

PubMed1988