Evaluation of Left Ventricual Asynchrony by Radionuclide Angiography: Comparison of Phase and Sector Analysis

Abstract The aim of this study was to assess the optimal method to evaluate asynchrony in equilibrium radionuclide angiography (RNA). METHODS: We studied 20 patients (14 males and 6 females, age range 25-60 yr) with RNA during atrial and sequential atrioventricular (AV) pacing, which increased left ventricular (LV) asynchrony. Both studies were performed at the same heart rate. Asynchrony was assessed either on phase images, by computing the standard deviation of the phase distribution (SD-P) and by sector analysis. Systolic and diastolic asynchrony were evaluated as the coefficient of variation of time to end systole (CV-TES) and time to peak filling rate (CV-TPFR) in four sectors. In addition, phase values were computed on time-activity curves from the same sectors, and their standard deviation (SD-Psec) was computed. RESULTS: During atrial pacing SD-P was 32.3 degrees +/- 6.7 degrees and did not change during AV pacing (32.1 degrees +/- 5.6 degrees, p = n.s.). Both CV-TES and CV-TPFR had a significant increase during AV pacing (from 7.7% +/- 3.9% to 11.5% +/- 6.4%, p < 0.01, and from 8.4 degrees +/- 5.8 degrees to 12.9 degrees +/- 6.7 degrees, p < 0.001). AV pacing led to a significant increase in SD-Psec (from 6.3 degrees +/- 4.0 degrees to 12.6 degrees +/- 9.7 degrees, p < 0.05). Moreover, reproducibility was assessed in 15 additional age-matched patients. The results of the reproducibility study indicate a better repeatability for CV-TES and CV-TPFR. CONCLUSIONS: The findings of this study suggest that sector analysis with calculation of indices of LV systolic and diastolic asynchrony is better suited for quantitation of LV temporal nonuniformity

Evaluation of left ventricular asynchrony byradionuclide angiography: comparison of phase and sector analysis.

The aim of this study was to assess the optimal method to evaluate asynchrony in equilibrium radionuclide angiography (RNA). METHODS: We studied 20 patients (14 males and 6 females, age range 25-60 yr) with RNA during atrial and sequential atrioventricular (AV) pacing, which increased left ventricular (LV) asynchrony. Both studies were performed at the same heart rate. Asynchrony was assessed either on phase images, by computing the standard deviation of the phase distribution (SD-P) and by sector analysis. Systolic and diastolic asynchrony were evaluated as the coefficient of variation of time to end systole (CV-TES) and time to peak filling rate (CV-TPFR) in four sectors. In addition, phase values were computed on time-activity curves from the same sectors, and their standard deviation (SD-Psec) was computed. RESULTS: During atrial pacing SD-P was 32.3 degrees +/- 6.7 degrees and did not change during AV pacing (32.1 degrees +/- 5.6 degrees, p = n.s.). Both CV-TES and CV-TPFR had a significant increase during AV pacing (from 7.7% +/- 3.9% to 11.5% +/- 6.4%, p < 0.01, and from 8.4 degrees +/- 5.8 degrees to 12.9 degrees +/- 6.7 degrees, p < 0.001). AV pacing led to a significant increase in SD-Psec (from 6.3 degrees +/- 4.0 degrees to 12.6 degrees +/- 9.7 degrees, p < 0.05). Moreover, reproducibility was assessed in 15 additional age-matched patients. The results of the reproducibility study indicate a better repeatability for CV-TES and CV-TPFR. CONCLUSIONS: The findings of this study suggest that sector analysis with calculation of indices of LV systolic and diastolic asynchrony is better suited for quantitation of LV temporal nonuniformity

La Funzione Ventricolare Sinistra nei Pazienti con Cardiopatia Ischemica Cronica: Relazione con lo Stato Perfusivo Miocardico

The aim of this study was the evaluation of left ventricular function compared to myocardial perfusion in patients with chronic coronary artery disease (CAD). Thirty-two patients with chronic CAD (27 men and 5 women, mean age 58 +/- 9 years) underwent radionuclide angiography and rest-redistribution thallium-201 (TI-201) single photon emission Computed Tomography (SPECT). Ejection fraction (EF, %), peak filling rate (PFR, end diastolic volume/second), and the coefficient of variation of the regional time to PFR (CV-TPFR, %) were computed. Patients with severe irreversible defects (i.e. with TI-201 uptake < 50%) had lower EF (42 +/- 7% vs 52 +/- 11%, p < 0.01) and lower PFR (1.9 +/- 0.4 vs 3.1 +/- 1.0, p < 0.0005) than those without. Patients with severe irreversible perfusion defects in the left anterior descending artery territory had lower EF (41 +/- 6% vs 50 +/- 11%, p < 0.01), lower PFR (1.8 +/- 0.3 vs 2.8 +/- 1.0, p < 0.005), and higher CV-TPFR (39 +/- 22 vs 13 +/- 7, p < 0.001) than those without. The results of the present study indicate that in patients with chronic CAD left ventricular systolic and diastolic function is more deteriorated when the left anterior descending artery is involved. Similarly, the presence of severe irreversible perfusion defects is clearly associated with significantly lower EF and PFR

Show me your tail, if you have one! Is inbreeding depression occurring in wildcats (Felis silvestris silvestris) from Italy?

Knowledge of genetic diversity is important to wildlife conservation because genetically depleted populations experience an increased risk of extinction. Mammalian carnivores are characterized by small and fragmented populations and low dispersal, so that genetic erosion can lead to the fixation of deleterious genes relatively quickly, leading to morphological abnormalities. Kinked tails and cowlicks are indicative of inbreeding depression and have been described in two wild cat species so far, the puma (Puma concolor) and the cheetah (Acinonyx jubatus). Here we report the first records of morphological abnormalities in five populations of the European wildcat (Felis silvestris silvestris) in Italy by using (1) camera-trapping and (2) necropsy of road-killed individuals assessed through genetic analysis. We collected 24,055 trap-nights from 251 cameras and recorded 566 wildcat detections, from which we identified 148 wildcats. Among these, 11 individuals had a kinked tail and four displayed brachyuria, whereas three wildcats from Sicily had cowlicks on the thorax. We recovered 28 road-killed wildcats and two of them (from Sicily and Friuli Venezia Giulia) had a kinked tail. Among these, one female with a kinked tail had a male foetus with a kinked tail, which proved that this characteristic was genetically inherited. We are unsure why brachyuria or cowlicks were not detected across all monitored wildcat populations, given we found kinked tails throughout Italy. The frequencies at which we have detected these abnormalities in wildcats are far lower than reports from Florida panthers (Puma concolor). Future research is needed to verify whether these abnormalities are also associated with low genetic diversity or other morphological defects which might lower fitness. We recommend a nationwide effort, using these techniques within a standardized sampling design, to further understand the status of the wildcat in Italy