Correlation between serum and fecal concentrations of reproductive steroids throughout gestation in goats

Non-invasive techniques such as the measurement of fecal steroids are now widely used to monitor reproductive hormones in captive and free-ranging wild-life. These methods offer great advantages and deserve to be used in domestic animals. The aim of the present study was to determine the endocrine profile of dairy goats throughout pregnancy by the quantification of fecal progestins and estrogens and assess its correlation with serum concentrations. Blood and fecal samples were collected weekly from 11 adult, multiparous goats, from mating through pregnancy and 2 weeks post-partum. The extraction of estradiol and progesterone fecal metabolites was performed by dilution in ethanol. The radioimmunoassay (RIA) in solid phase was used to quantify serum 17beta-estradiol (estradiol) and progesterone, as well as their fecal metabolites. The mean concentrations of both fecal and serum estradiol started to increase between weeks 7 and 11, reached peak values near parturition and then decreased sharply (range: 19.8+/-5.8 ng/g of feces to 608.6+/-472.4 ng/g of feces and 0.007+/-0.005 ng/ml to 0.066+/-0.024 ng/ml). An increase in both fecal and blood progestagens occurred in the second week, mean concentrations remained greater until week 20, and then decreased in the last week of gestation and 2 weeks post-partum (range: 108.8+/-43.6 ng/g of feces to 3119.5+/-2076.9 ng/g of feces and 0.12+/-0.04 ng/ml to 13.10+/-4.29 ng/ml). The changes in blood and fecal hormone concentrations were analyzed and compared throughout gestation for each single goat, for each breed and for the whole group. Results indicated that matched values of serum and fecal hormone concentrations were correlated (r=0.79; p<0.001 for progesterone and r=0.84; p<0.001 for estradiol mean concentrations in the whole group). Regression analysis showed that logarithmic model allows significant prediction of serum from fecal concentrations with an R(2)=0.729 (y=0.013ln x-0.021) for estradiol and R(2)=0.788 (y=3.835ln x-18.543) for progesterone. Neither fecal nor serum concentrations were affected by the breed but a significant effect of the number of fetuses on progestin concentrations was found. Therefore, the profiles of progesterone and estradiol fecal metabolites reflect the serum concentrations of the same hormones in pregnant goats.

[Long-term clinical assessment of single-lead VDD electric stimulation]

BACKGROUND

During the last decade single lead VDD pacing has been progressively affirmed as an electrotherapy of choice in patients with advanced atrioventricular block without alterations of the sinus function. It combines the benefits of P-synchronous ventricular pacing with an easy implant procedure when compared to the conventional DDD approach. The aim of this study was to evaluate the validity of such an approach in a large population of patients, all implanted in a single center.

METHODS

From 1987 up to now, 317 patients, all affected by advanced atrioventricular block and without sinus node dysfunction, were implanted in our center with a single lead VDD pacemaker. During follow-up the persistence of a proper atrioventricular synchronization was assessed and evaluated.

RESULTS

The mean follow-up was 3.9 +/- 2.7 years/patient (range 6-138 months). The 94.6% of implanted systems maintained the normal VDD pacing function. Permanent reprogramming in VVI mode was necessary in 17 patients (5.36%); in 12 (3.78%) because of chronic atrial fibrillation and in 5 (1.63%) for loss of atrial sensing. The percentage of atrial synchronization was optimal (> 98%) and acceptable (> 95%) in 81% and 19% of patients, respectively. Episodes of paroxysmal atrial fibrillation occurred in 3 patients. Neither inhibition by myopotentials nor occurrence of sinus node disease was observed during follow-up. These results are in accordance with those reported by previous studies, performed on a smaller population or on a multicenter basis, and are comparable with the results reported for conventional DDD pacemaker.

CONCLUSIONS

Our results confirm the high reliability of the single lead VDD pacing system concerning the long-term persistence of a proper atrioventricular synchronization. Data showed above enforce our opinion that this pacing approach should be considered the treatment of choice in patients with advanced atrioventricular block and preserved sinus node function.

[The long-term effects of dual-chamber stimulation in 8 patients with hypertrophic obstructive cardiomyopathy and symptoms refractory to medical therapy]

BACKGROUND

The issue of DDD pacing as a therapeutic option for patients with obstructive hypertrophic cardiomyopathy is still under debate. Moreover, some authors stress the concept of the placebo effect of electrical therapy in this particular setting.

METHODS

We retrospectively evaluated 8 symptomatic patients with obstructive hypertrophic cardiomyopathy despite medical therapy, who underwent DDD pacemaker implantation as an adjunctive therapeutic strategy. All patients were evaluated with a two-dimensional/Doppler echocardiogram at baseline, shortly after the beginning of DDD pacing and at follow-up. In 3 patients dobutamine stimulation was necessary to elicit the intraventricular gradient.

RESULTS

At follow-up (21 +/- 19 months, range 1-54 months) the peak gradient declined from 86 +/- 27 to 34 +/- 27 mmHg (55.2%). In 4 patients the peak gradient sharply declined after pacemaker implantation with active pacing and remained stable throughout the follow-up. In 2 patients we noted a continuous reduction in the peak gradient during the follow-up, while in 2 patients it returned to baseline values after 1 year and 1 month, respectively, despite an early reduction with DDD pacing. All patients experienced symptomatic amelioration throughout the follow-up. Two patients developed angina at the end of our observation together with an increase in the peak gradient.

CONCLUSIONS

We believe that DDD pacing may be considered as a practical therapeutic option for patients with obstructive hypertrophic cardiomyopathy who would otherwise be regarded as candidates for surgery.

Impact of recombinant human erythropoietin treatment on left ventricular hypertrophy and cardiac function in dialysis patients

The results of anemia correction by recombinant human erythropoietin (rHuEPO) therapy with regard to cardiac function and left ventricular hypertrophy in dialysis patients are controversially discussed. The aim of the study was to assess the effects of therapy rHuEPO on cardiac morphology and function in dialysis patients. We studied 11 clinically stable hemodialysis patients with severe renal anemia (hematocrit <27%) and increased left ventricular mass index (LVMi) with no history of coronary or valvular heart disease, systemic disease, severe hyperparathyroidism, hypertension stage 2 or higher, transfusion-dependent anemia, and concurrent rHuEPO treatment. The patients were treated with rHuEPO administered subcutaneously once or twice weekly at a mean dose of 80 +/- 31 IU/kg week until the hematocrit was >30% and underwent a complete Doppler echocardiographic study at baseline and at follow-up (after 12.2 +/- 2.9 months). At follow-up, ejection fraction and fractional shortening significantly increased from 62.7 +/- 13.8 to 67.8 +/- 9. 7% (p < 0.05) and from 35.5 +/- 9.8 to 39.4 +/- 7.1% (p < 0.05), respectively, whereas mean velocity of circumferential fiber shortening demonstrated a trend towards amelioration from 1.18 +/- 0. 23 to 1.27 +/- 0.27 circ/s (n.s.). LVMi and morphological data remained unchanged throughout the study. Nevertheless, LVMi changes showed two different behaviors with respect to baseline values: in 6 patients with higher baseline values, LVMi decreased from 229 +/- 36 to 191 +/- 45 g/m2 (p < 0.05), while it worsened in 5 patients with less marked LVMi, increasing from 141 +/- 32 to 186 +/- 40 g/m2 (p < 0.05). Our data demonstrate that partial correction of renal anemia with rHuEPO therapy seems to improve cardiac performance and to induce a regression of left ventricular hypertrophy, particularly in patients with greater baseline hypertrophy, ultimately confirming the multifactorial pathogenesis of left ventricular hypertrophy.

Doppler echocardiographic assessment of left ventricular isovolemic relaxation flow

BACKGROUND

It is not infrequent to observe a peculiar intraventricular relaxation flow (IRF) pattern during the isovolumic relaxation time (IRT), especially in patients (pts) with left ventricular hypertrophy (LVH). This is even more likely in pts with hypertrophic obstructive cardiomyopathy and in VVI-paced pts. Despite these observations, the prevalence and clinical relevance of this finding have not been evaluated thoroughly and systematically in a consecutive series of patients.

METHODS

Ninety-two consecutive pts underwent a conventional Doppler echo study for the evaluation of systolic and diastolic function (fractional shortening, EF, E and A wave velocity, duration and ratio, and IRT). of these, 42 pts had LVH, 14 had mitral regurgitation (MR) with depressed EF, 8 had CAD with depressed EF and 28 were normal subjects. IF was searched for during the evaluation of IRT and its duration, velocity and integral were measured when noted.

RESULTS

Fifty-six patients (61%) showed an IRF at Doppler examination. Of these, fifteen were normal subjects (53%) and 34 (81%, p = 0.03 vs normal) were hypertensive pts. Among pts with depressed EF, only two of 14 with MR and 5 of 8 with no MR showed an IRF (14 vs 62%; p = 0.032). When evaluating LV function, we observed that pts with an IRF had a larger atrial filling fraction, a longer isovolumic relaxation time and a higher ejection fraction with respect to pts with no IRF (respectively, 40 +/- 13% vs 30 +/- 13%, p = 0.005; 108 +/- 23 ms vs 77 +/- 22 ms, p = 0.0001; 70 +/- 14% vs 61 +/- 16%, p = 0.01).

CONCLUSIONS

Our data confirm that IRF may be observed in healthy subjects and may be due to an asynchronous relaxation of the LV during IRT, in consideration of a higher prevalence of a greater atrial filling fraction in pts with IF as compared to those in whom this Doppler signal is absent. Moreover, IRF is more frequent in pts with LVH and is rare in pts with MR (predominantly due to a very short isovolumic relaxation time).

Identification of viable myocardium by nitrate echocardiography after myocardial infarction: comparison with planar thallium reinjection scintigraphy

BACKGROUND

The aim of this study was to validate a new diagnostic tool, nitrate echocardiography (NE), for the identification of viable noncontracting myocardium in patients with a history of prior myocardial infarction (MI). Nitroglycerin (NTG) may be useful for this purpose for its peculiar pharmacodynamic action and may represent an option other than dobutamine echocardiography for the detection of hibernating segments in the presence of severely reduced coronary reserve.

METHODS

Twenty selected patients (pts) with an old MI were studied with NE and planar thallium scintigraphy with reinjection. NE was performed by administering i.v. NTG starting at 0.4 mcg/kg/minute with equal increments every five minutes up to 2 mcg/kg/minute or to early interruption of the test (decrease of systolic blood pressure > or = 20% or improvement of previously akinetic segments). Left ventricular wall motion was analyzed by dividing the left ventricle (LV) into 16 segments, and a wall motion score index (WMSI) was calculated. Thallium images were obtained at peak exercise, at four hours, and after reinjection. Myocardial viability was defined as an improvement in thallium uptake after reinjection in fixed defects.

RESULTS

Basal echo demonstrated 74 akinetic segments; of these 21 (28%, 11 pts) showed improved contractility during NTG infusion at a mean dose of 0.87 +/-0.33 mcg/kg/minute. WMSI decreased from 1.69 +/- 0.29 to 1.46 +/- 0.31 (P = .001). The only hemodynamic response was a drop in systolic blood pressure (136 mmHg to 124; P = .02). Thallium studies showed 29 segments with a four-hour reversible defect and 79 segments with a four-hour fixed defect; of the latter, 14 regions demonstrated improvement in tracer uptake after reinjection (17.7%; 10 pts). Nine pts had a positive echo and thallium study, while 8 showed no improvement either during NE or after thallium reinjection. Two pts had a false-positive nitrate echocardiogram. Therefore, according to an echo/thallium study match, sensitivity, specificity, and accuracy are 90%, 80%, 85%, respectively.

CONCLUSION

NE is a reliable and low-cost method for the detection of viable noncontracting myocardium in selected patients with CAD but needs further validation for widespread application.

Acute myocardial infarction shortly after a normal exercise stress test. Case reports

The authors describe 3 cases of AMI occurring shortly after a negative bicycle ergometer stress test. These cases represent an unfortunate but extremely rare complication of a relatively safe diagnostic procedure. The authors also focus on the pathogenesis of the ischemic event, which may be attributed either to intraplaque hemorrhage or to platelet aggregation, both exercise-induced. The prevalence of AMI in this paper (0.06%) is similar to the data described in literature.

Bifascicular block complicating blunt cardiac injury. A case report and review of the literature

A thirty-five-year-old horse trainer presented to the emergency room of the authors' hospital with minimal nonpenetrating chest injury after having been kicked by a horse. No rib or sternum fractures were demonstrated. The admission ECG demonstrated a right bundle branch block and a left anterior hemiblock that were previously absent. The authors are aware of only two similar reports, but analogous conduction disturbances might have been classified as intraventricular conduction defects. The rarity of these defects may be explained by the anatomic pathways of the bundle of His and its bifurcations.

[The echo-nitrate test for the detection of viable myocardium after a myocardial infarct: a comparison with delayed-acquisition thallium scintigraphy]

BACKGROUND

The aim of this study was to evaluate the ability of echocardiography, associated with nitroglycerin infusion, in the detection of myocardial viability in patients with recent infarction.

PATIENTS AND METHODS

Fourteen patients (11 male, 3 female, mean age 59 +/- 8 years) with first acute myocardial infarction (12 Q wave, 2 non-Q wave) underwent predischarge (18 +/- 3 days) nitrate echocardiography. All patients underwent delayed planar thallium scintigraphy within four weeks from AMI. Nitrate echocardiography was performed with a nitroglycerin infusion starting from 0.4 mcg/Kg/min every 5 minutes up to 2.0 mcg/Kg/min; the test was terminated with an improvement of wall motion abnormalities or with a drop of systolic blood pressure > or = 20%. Wall motion abnormalities were evaluated with a 16-segment wall motion score index (WMSI). Thallium was performed after a symptom-limited exercise test, after 3 and 24 hours. The left ventricle was divided in 15 regions. Thallium was considered the gold standard for myocardial viability.

RESULTS

Basal echo identified 59 dyssynergic segments: of these, 12 (20%-6 patients) showed improvement in contractility during nitrate echocardiography at a mean dose of 0.9 +/- 0.3 mcg/Kg/min. WMSI decreased from 1.42 +/- 0.22 to 1.27 +/- 0.13 (p = 0.022), with no significant change of haemodynamic data (mean systolic blood pressure from 125 to 112 mmHg; mean heart rate from 66 to 76 beats/min; mean rate/pressure product from 8415 to 8848; all p = ns). Thallium scintigraphy showed 40 fixed defects (19%-7 patients) and 10 (4.7%-7 patients) late reversible defects. 20% of the 3-hour fixed defects improved at 24-hour imaging. 5/7 patients with echo improvement had 24-hour reversible defects, while 6/7 with no WMSI improvement had 24-hour fixed defects. Therefore, nitrate echocardiography demonstrated 71% sensitivity, 86% specificity, 83% positive predictive value, 75% negative predictive value and 78% accuracy.

CONCLUSIONS

Nitrate echocardiography may be a feasible and low cost method in the detection of myocardial viability after myocardial infarction, but awaits further validation.

[Pregnancy in users of heart valve prostheses]

The observation of pregnancy in women with a mitral and aortic valvular prosthesis, allows the authors to point out the high maternal and fetal risk and to show the therapeutical treatment chosen. The obtained results, confirm the effectiveness of the anticoagulant treatment by heparin and of delivery by cesarean section.

[Aortic pseudo-valvular image with diastolic eccentricity of the semilunaris. A specific sign of aortic dissection?]

M-mode and two-dimensional echocardiograms were obtained in a patient with aortic dissection (De Bakey type 1). The M-mode echocardiogram showed an image resembling to an aortic valve with a left coronary cusp and eccentric diastolic echoes. The M-mode and two-dimensional echocardiograms recorded at a more distal level showed that this image was produced by the systo-diastolic movements of the torn intima. Such an echocardiographic finding should suggest the presence of an aortic dissection.