Assessment of diastolic function in normal and hypertrophied hearts: comparison of Doppler echocardiography and M-mode echocardiography

Left ventricular (LV) filling was examined by Doppler and M-mode echocardiography in 24 patients with LV hypertrophy (five with aortic stenosis, six with hypertrophic cardiomyopathy, and 13 with LV hypertrophy secondary to systemic hypertension) and in 18 normal subjects. Patients with LV hypertrophy had significantly lower Doppler-determined peak filling rates (218 +/- 17 vs 288 +/- 66 cc/sec, p less than 0.01), but M-mode determined peak rate of chamber enlargement and normalized peak rate of chamber enlargement did not differ significantly between groups. Doppler measures of the ratio between early and late filling were significantly depressed in patients with LV hypertrophy and correlated inversely with age in the normal subjects. The M-mode derived normalized peak rate of chamber enlargement and the Doppler-derived normalized peak filling rate correlated weakly, but significantly, when both groups were combined (r = 0.56, p less than 0.01). Thus Doppler measurements can detect abnormalities of LV filling in patients with LV hypertrophy. These abnormalities are present when M-mode filling indices and systolic function are still normal.

Left ventricular systolic and diastolic flow abnormalities determined by Doppler echocardiography in obstructive hypertrophic cardiomyopathy

To analyze the relation of systolic anterior motion (SAM) of the mitral valve, peak left ventricular (LV) outflow tract velocity, aortic flow and mitral flow, 17 patients with obstructive hypertrophic cardiomyopathy (HC) (8 men, 9 women), aged 19 to 88 years (mean 45), were studied using M-mode and 2-dimensional echocardiography and pulsed and continuous-wave Doppler echocardiography and results were compared with those from 18 age-matched normal subjects. SAM was present in all patients with HC and absent in normal subjects. Time to peak outflow velocity as a percentage of LV ejection time was 63% in patients with HC and 29% in normal subjects (p less than 0.001). In 13 patients, time from the R-wave peak to the closest approximation of the mitral valve to the ventricular septum or initial contact during SAM was determined and was 242 +/- 66 ms and time from the R-wave peak to the peak LV outflow tract velocity was 242 +/- 73 ms (r = 0.90). In 11 patients time from the R-wave peak to cessation of flow in the ascending aorta was measured and was 286 +/- 80 ms; time from the R-wave peak to the peak LV outflow tract velocity was 246 +/- 75 ms. The ratio of early to late diastolic filling velocities of the left ventricle was 1.47 +/- 0.40 in the normal subjects and 1.26 +/- 0.84 in patients with HC (difference not significant). The early to late ratio of the 12 patients without mitral regurgitation was 0.99 +/- 0.52 (p less than 0.01 vs normal subjects).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of aging on left ventricular diastolic filling in normal subjects

To determine the effect of aging on left ventricular filling, mitral valve flow was evaluated with real-time (color flow) and conventional pulsed Doppler echocardiography in 32 subjects, aged 24 to 68 years, who had no evidence of cardiovascular disease. The diameter of mitral valve flow was measured in early and late diastole in the apical 4-chamber view. Transmitral velocities were measured in early and late diastole with pulsed Doppler echocardiography. The early flow diameter was significantly smaller in patients older than 50 than in those aged 20 to 29 years (p less than 0.05), while atrial flow diameter was significantly larger in patients older than 50 than in those aged 20 to 29 years (p less than 0.05). The ratio of early flow diameter to atrial flow diameter was 1.85 +/- 0.33 in patients 20 to 29 years old and 1.17 +/- 0.28 in those older than 50 (p less than 0.001). The ratio of early to atrial diastolic velocities was 1.98 +/- 0.53 in the younger patients and 1.07 +/- 0.41 in those older than 50 years (p less than 0.001). The ratio of early flow diameter to atrial flow diameter decreased significantly with aging, and this decrease had a negative correlation with aging (r = -0.64). Qualitatively, in these normal subjects, early diastolic flow filled the ventricle centrally, while with atrial contraction, flow entered the ventricle toward the posterolateral wall and was associated with flow moving toward the aortic valve along the ventricular septum.(ABSTRACT TRUNCATED AT 250 WORDS)

"En bloc" excision of diabetic membranes

We treated 16 eyes with diabetic tractional retinal detachment with a new method of surgical dissection whereby diabetic preretinal membranes and adherent posterior hyaloid were excised and removed as a single unit. This method differs from previously reported methods of diabetic membrane dissection by utilizing the posterior hyaloid to lift and immobilize the membrane as the membrane is excised with horizontally cutting scissors. The preservation of the posterior hyaloid facilitates the separation of the membrane from the retina. Fibrovascular proliferation was more completely removed and bleeding was less than with membrane sectioning techniques. The major surgical complication was posterior retinal break (seven eyes), but with near complete relief of traction all breaks were successfully treated with gas tamponade and laser photocoagulation. Thirteen retinas were completely reattached with a minimum follow-up of four months. One eye developed an extramacular tractional retinal detachment, and two eyes developed peripheral (retrolenticular) fibrovascular proliferation. Eleven eyes had 5/200 or better visual acuity.

Management of fibrin pupillary-block glaucoma after pars plana vitrectomy with intravitreal gas injection

After pars plana vitrectomy and fluid-gas exchange, two patients developed fibrin membranes across the pupillary space resulting in pupillary block and subsequent glaucoma. In one case the angle was closed; in the second case the angle was open because of gas in the anterior chamber. In both cases the argon laser made permanent openings in the fibrin pupillary membrane that relieved the pupillary block.

Parathyroid hormone secretion: effect of estradiol and progesterone

Previous studies have shown that estrogen therapy in postmenopausal women results in an increase in serum immunoreactive parathyroid hormone (iPTH) levels. It has been assumed that this effect of estrogen on PTH secretion is indirect, being mediated via mild hypocalcemia resulting from an inhibition of bone resorption. We evaluated the direct effect of 17 beta-estradiol (E2) and of progesterone (Prog) on secretion of PTH from bovine parathyroid tissue in vitro. Both E2 and Prog caused a significant stimulation of PTH secretion within one hour, which was progressive for the three-hour observation period. The responses were dose-related from 10(-7) to 5 X 10(-10) mol/L. There was no PTH response to 10(-7) mol/L alpha-E2, 3-methoxy estriol, estrone, testosterone, or 20-alpha-hydroxy progesterone, indicating specificity of the responses to E2 and Prog. There was a minimal PTH secretory response to 10(-6) mol/L cortisol and 10(-6) mol/L estrone. The E2 receptor antagonist tamoxifen did not inhibit the E2 effect on PTH secretion. This observation plus the rapid PTH response suggests that this hormonal effect may not be via the conventional intracellular E2 receptor. Therefore, E2 and Prog can stimulate PTH secretion by rapid, direct, and specific effects on parathyroid cells. These gonadal hormones may, therefore, be important in calcium homeostasis via their direct stimulatory effect on PTH secretion.

The effect of vincristine on parathyroid hormone release and on the parathyroid cell microtubular structures in the intact rat

The effect of vincristine on immunoreactive parathyroid hormone (iPTH) release and parathyroid cell microtubular structures was evaluated in intact, unanaesthetized, and unrestrained rats with indwelling catheters. In overnight fasted rats, blood samples were collected before and at 30, 60 and 120 min after iv vincristine administration in low dosage (0.15 mg/kg) or in higher dosage (0.5 mg/kg) or vehicle (controls) for serum iPTH and calcium determinations. Mean baseline serum iPTH and calcium concentrations were similar in the vincristine-treated and the control rat. Following the low dose vincristine treatment, serum iPTH slightly but significantly declined to 89 +/- 5% at 30 min and remained at this low level at 60 and 120 min as compared to those observed in control rat. Similarly, iPTH concentrations after higher doses of vincristine were also significantly decreased to 87 +/- 4% at 30 min and to 83 +/- 4% at 60 min, and 86 +/- 7% at 120 min as compared to those observed in the control rat. Serum calcium concentrations were similar in the vincristine-treated and control rats. In the next study, each of the rats received vincristine and vehicle in a random order, 10 days apart. In this study also, mean serum iPTH significantly declined to 85 +/- 7% at 60 and 120 min during vincristine treatment as compared with those observed during the vehicle treatment in the same rats. Parathyroid glands were removed from rats between 60 and 120 min after vincristine or vehicle treatments for electron microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)

Diltiazem as an adjunct to cold blood potassium cardioplegia: a clinical assessment of dose and prospective randomization

Diltiazem was evaluated as an adjunct to cold blood potassium cardioplegia in 63 patients undergoing elective coronary artery bypass grafting. The dual-phase study compared incrementally increasing doses (50, 100, and 150 micrograms/kg) of diltiazem using a single-blind, randomized schedule with an equivalent volume of placebo added to each of three infusions of cold (10 degrees C +/- 2 degrees C) blood containing potassium chloride at 25 mEq/L for the initial infusion (400 ml) and at 12 mEq/L for the next two infusions (300 ml each). Observations included a number of operative variables, creatine kinase (CK)-MB curves, two-dimensional echocardiography, and pulsed Doppler sonography before operation and on postoperative days 1 and 5. Pulmonary artery thermistor catheter responses were observed for 16 hours postoperatively, as were left ventricular micromanometer-tipped catheter responses in 7 patients. As the dose of diltiazem was increased, there was increasing time to atrioventricular node refunction (23.6 to 62.0 minutes). Diltiazem at 100 micrograms/kg (D-100) resulted in a significantly lower peak CK-MB activity than its placebo. Peak - dp/dt increased in treated patients and decreased in patients given the placebo. The cardiac index in D-100 patients was greater on the first postoperative day than preoperatively. The stroke index returned to the control level by the fifth postoperative day in D-50 and D-100 patients only, and it remained depressed in placebo patients. Although few benefits were realized from the addition of diltiazem to cold blood potassium cardioplegia, there was dose-related prolongation of the atrioventricular node recovery time, which required cardiac pacing and thus was associated with its attendant risks.

Evaluation of left ventricular function during upright exercise: correlation of exercise Doppler with postexercise two-dimensional echocardiographic results

The relationship of regional and global left ventricular function to aortic flow dynamics during exercise was determined in 14 normal subjects and 14 patients with coronary artery disease. Doppler and two-dimensional echocardiographic studies were performed before, during, and immediately after an exercise test by the Bruce protocol. Two-dimensional echocardiography was used to determine the ejection fraction and new wall motion abnormalities. The peak ejection velocity, stroke index, and cardiac index were calculated from the pulsed Doppler tracing. In normal subjects the ejection fraction increased significantly (p less than .001) from rest (0.51 +/- 0.07) to peak exercise (0.61 +/- 0.07), while the response in coronary patients was blunted (0.49 +/- 0.11 vs 0.48 +/- 0.16). Similarly, the change in peak ejection velocity throughout exercise in normal subjects (from 0.71 +/- 0.12 to 1.50 +/- 0.35 m/sec) was significantly (p less than .01) greater than that in patients with coronary artery disease (from 0.61 +/- 0.13 to 0.90 +/- 0.29 m/sec). There was a good correlation between the percent change in peak ejection velocity and the percent change in ejection fraction from rest to peak exercise in the entire study group (rs = .64) and in the patients with coronary artery disease (rs = .84). These preliminary data suggest that exercise-induced changes in Doppler echocardiographic variables may offer a potential adjunct in the evaluation of patients with ischemic heart disease.

A revision of the genus Nascioides Kerremans (Coleoptera : Buprestidae)

The buprestid genus Nascioides Kerremans is defined, and a key and figures to the 19 species are given. Eight new species are described: Nascioides bicolor, elessarella, elderi, falsomultesimus, macalpinei, nulgarra, storeyi and walfordi. Lectotypes are designated for: Nascioides carissimus (Waterhouse), N. costatus (Carter), N. enysi (Sharp), N. multesimus (Olliff), N. mundus (Olliff), N. parryi (Hope), N. tillyard (Carter) and N. viridis (Macleay). Nascioides parryi (Hope) is designated as type-species and the previously established synonymy [Nascioides saundersi (Hope) =N. parryi (Hope)] is upheld.

Structural Studies of Technetium Complexes. X. The Crystal-Structure of Tetraphenylarsonium Hexakis(Isothiocyanato)Technetate(IV)-Dichloromethane (1/1)

The crystal structure of [AsPh4]2 [ Tc (NCS)6].CH2Cl2 has been determined by single-crystal X-ray diffraction methods at 23 � 1�C . Crystals are tetragonal, space group I4/m, with a 11.523(5), c 22.43(2) �, and Z 2. Diffraction data from two different crystals were analysed and in both cases disorder was present in the crystal lattices. Full-matrix least-squares refinement gave a final R value of 0.073 for 1188m independent reflections. The [TC(NCS)6]2- anion has an octahedral structure with the technetium(1V) atom situated on a site of 4/m symmetry. The Tc -N bond lengths are 2.00(1) and 2.01(1) Ǻ with N- Tc -N angles of exactly 90�. Two of the Tc -NCS groups are constrained by the crystal symmetry to be perfectly linear, while for the remaining four Tc -NCS groupings the Tc -N-C and N-C-S angles are 175.9(9)� and 175.3(10)� respectively.

Quantitative evaluation of aortic insufficiency by continuous wave Doppler echocardiography

To assess the usefulness of continuous wave Doppler echocardiography in the evaluation of aortic insufficiency, the aortic regurgitant flow velocity pattern obtained with continuous wave Doppler examination was compared with the results of aortography and conventional pulsed Doppler techniques in 25 individuals with aortic insufficiency. The diastolic deceleration slope as measured from the continuous wave tracing was significantly different among subgroups of patients with mild (1.6 +/- 0.5 m/s2), moderate (2.7 +/- 0.5 m/s2) and severe (4.7 +/- 1.5 m/s2) aortic insufficiency as determined from aortography. Deceleration slopes greater than 2 m/s2 separated individuals with moderate and severe insufficiency from those with mild insufficiency. Similar findings were seen when comparing the pressure half-time method of diastolic velocity decay with the more severe grades of aortic insufficiency exhibiting the shortest pressure half-times. There was also a high correlation (r = 0.85) between the deceleration slope measured by continuous wave Doppler recordings and the grade of insufficiency as assessed by pulsed Doppler echocardiography. End-diastolic velocities correlated poorly (r = 0.28) with catheter-measured end-diastolic pressure difference between the aorta and the left ventricle. These findings demonstrate that the aortic regurgitant flow pattern by continuous wave Doppler echocardiography may be useful in quantitating the degree of aortic insufficiency by assessing the rate with which aortic and left ventricular pressures equilibrate during diastole.

Left ventricular diastolic function in weight lifters

Concentric left ventricular (LV) hypertrophy and asymmetric septal hypertrophy have both been described in weight lifters, but diastolic filling, which is abnormal in pathologically hypertrophied ventricles, has not been investigated in such subjects. Accordingly, pulsed Doppler examination of LV inflow, M-mode and 2-dimensional echocardiography were performed in 16 competitive weight lifters and 10 age-matched male control subjects. Peak and mean filling rates were determined in milliliters per second as the product of the cross-sectional area of the mitral anulus and the Doppler-derived peak early and mean transmitral inflow velocities, respectively. Rapid filling index was defined as peak filling rate divided by mean filling rate. Flow velocity integrals of the early and atrial diastolic filling phases were also measured. LV end-diastolic volume and ejection fraction were measured using 2-dimensional echocardiography. Weight lifters had significantly higher LV end-diastolic volume (181 +/- 50 vs 136 +/- 40 ml, p less than 0.05) and dimension (5.6 +/- 0.6 vs 5.1 +/- 0.5 cm, p less than 0.05), and posterior wall thickness (0.9 +/- 0.2 vs 0.8 +/- 0.1, p less than 0.05); however, after correction for body surface area there was no significant difference in these values. Weight lifters had significantly higher LV mass (241 +/- 70 vs 165 +/- 29, p less than 0.02) and LV mass index (114 +/- 29 vs 87 +/- 15 g/m2, p less than 0.05). There was no significant difference between the weight lifters and control subjects in rapid filling index, early to late integral ratio or ejection fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Development of traction retinal detachments following intravitreal injections of retinal Muller and pigment epithelial cells

We injected varying numbers of retinal Muller glia into the rabbit vitreous in an established model of traction retinal detachment. We used indirect ophthalmoscopy to observe the changes elicited during the following 1 month. Although the severity of the tractional changes increased with increasing numbers of the glial cells, the pathology produced stabilized within the 1st week of injury. Muller glia were less effective at eliciting retinal detachments than retinal pigment epithelial cells (RPE) or mixtures of glia and RPE. Intravitreal tissue membranes derived from the glia differed morphologically from those derived from RPE. The glial membranes had fewer fibroblast-like cells, synthesized less extracellular matrix, and showed lower intravitreal cell proliferation, as determined by 3H-thymidine radioautography. Our findings indicate that membranes composed only of Muller glial cells promote less severe retinal pathology than those membranes composed of RPE or mixed cell types.

Management of postoperative suprachoroidal hemorrhage with continuous-infusion air pump

Seven patients suffered delayed nonexpulsive suprachoroidal hemorrhages following filtration procedures. Six of seven eyes were aphakic, while the seventh had a subluxated lens associated with aniridia. In six of the seven cases, the hemorrhagic choroidal detachments completely filled the posterior segment, and visual acuity was reduced to light perception only. Surgical drainage of the hemorrhages was accomplished through one or two sclerotomies with simultaneous air insufflation of the eye through a limbal needle attached to a continuous-infusion air pump. With this technique, visual acuity was restored to a level equal to or better than the prefiltration acuity in five of seven patients. One patient suffered a slight decline in acuity from 20/60 to 20/100, and another patient's visual acuity declined from finger counting at 5 cm to hand motions.

Prolonged effect of estradiol on calcitonin secretion

Incubation of thyroparathyroid gland from 8-day-old rats with estradiol (10(-7) and 10(-9) M) and progesterone (10(-9) and 3 X 10(-10) M) resulted in stimulation of CT secretion. The effect of the gonadal steroids on CT secretion occurred at near physiological concentrations and persisted for at least 73 h. The studies demonstrate that exposure to gonadal steroids results in direct and prolonged stimulation of CT secretion. Therefore the decrease in bone resorption observed after the administration of gonadal steroids in vivo may at least in part be mediated via stimulation of CT secretion.

Clinical results of titanium retinal tacks with pneumatic insertion

We used titanium retinal tacks inserted with a pneumatic instrument for retinal fixation in 11 operative procedures in ten eyes with complicated retinal detachments. Titanium was selected for permanent implantation because of its documented biologic tolerance. No intraoperative or postoperative complications related to the tacks were encountered. Three tacks, one 0.7 mm in length and two 1.6 mm in length, became dislodged postoperatively; 50 permanently implanted tacks, each 1.6 mm in length, remained in place after a mean follow-up of five months. Retinal reattachment at the end of the follow-up period was achieved in eight eyes and useful visual function was obtained in three eyes. Titanium retinal tacks are useful when immediate retinal fixation is required either temporarily or permanently to prevent retraction and detachment of the retina until adjunctive diathermy, cryopexy, or photocoagulation becomes effective.

Penetrating keratoplasty after placement of a temporary keratoprosthesis during pars plana vitrectomy

Five eyes of five patients with opaque corneas underwent penetrating keratoplasty after pars plana vitrectomy. In each case, the Landers-Foulks temporary keratoprosthesis provided visualization of the vitreous cavity and retina, allowed successful removal of hemorrhagic vitreous, and permitted retinal reattachment. Corneal grafts remained clear in two eyes; three grafts developed stromal edema. Useful postoperative vision was achieved in two eyes. However, proliferative vitreoretinopathy, postoperative hypotony, atrophia bulbi, and corneal edema resulted in poor vision in three eyes.

Effect of coronary artery disease on Doppler-derived parameters of aortic flow during upright exercise

Recent advances in Doppler echocardiography have made possible noninvasive determination of stroke volume, cardiac output and peak ejection velocity at rest. To determine the ability of Doppler to measure these variables and the effect of altered left ventricular (LV) function during upright treadmill exercise, 20 normal subjects (group I) and 17 patients with coronary artery disease (CAD) (group II) were studied. Stroke index response was similar in both groups. The increase in cardiac index was more rapid in group I subjects and reached a higher peak value at maximal exercise (8.6 +/- 2.5 vs 5.5 +/- 2.2 liters/min, p less than 0.001). Peak ejection velocity increased rapidly during exercise in group I subjects; it increased much less in group II patients. Differences were significant at each stage of exercise. Peak ejection velocity was 1.56 +/- 0.32 and 0.89 +/- 0.26 m/s in group I vs group II patients, respectively, at maximal exercise. Three responses were seen in group II subjects. Three patients, all with 1-vessel CAD and normal LV function at rest, showed a normal response, with an increase in peak ejection velocity of at least 80% (type I response). In 8 patients peak ejection velocity increased less than 80% (type II response) and in 6 patients it decreased at maximal exercise (type III). Type II and III responses were seen in patients with more severe CAD and LV dysfunction at rest. These data show a progressive difference in Doppler-derived variables in exercise between normal subjects and patients with CAD, which is greatest in patients with LV dysfunction at rest and multivessel CAD.

Effects of estradiol and progesterone on calcitonin secretion

Estrogen therapy has been used to inhibit bone resorption and prevent osteoporosis in postmenopausal women. Previous studies have disagreed as to whether the mechanism of estrogen action involves stimulation of calcitonin (CT) secretion. We evaluated the direct effects of 17 beta-estradiol (E2) and progesterone (Prog) on CT secretion from the thyroid C cells of 8-day-old rats in vitro. Both E2 and Prog caused a significant stimulation of CT secretion within 1 h, which was progressive for the 3-h observation period. The responses were dose related from 10(-7) to 5 X 10(-10) M. There was no CT response to 10(-7) M alpha-estradiol, estriol, 3-methoxyestriol, estrone, testosterone, or 20 alpha-hydroxyprogesterone, indicating specificity of the responses to E2 and Prog. There was a minimal CT secretory response to 10(-6) M cortisol. The E2 receptor antagonist tamoxifen did not inhibit the E2 effect on CT secretion. This observation plus the rapid CT response suggest that this hormonal effect may not be via the conventional intracellular E2 receptor. Therefore, E2 and Prog can stimulate CT secretion by rapid, direct, and specific effects on the thyroid C cell. The gonadal hormones may, therefore, be important in inhibiting bone resorption via their direct stimulatory effect on CT secretion.

Treatment of intraocular lymphoma with high-dose Ara-C

Ocular lymphoma is an uncommon clinical entity with a propensity for intracranial extension. Palliation has been reported following radiotherapy, but the ultimate prognosis is poor, and significant treatment-related morbidity is common. Recent pharmacokinetic studies have suggested that sustained therapeutic drug concentrations are achievable in cerebrospinal fluid after systemic administration of high-dose cytosine arabinoside (Ara-C). These data led the authors to attempt treatment of a case of recurrent ocular lymphoma with high-dose Ara-C. Therapeutic drug levels were documented in intraocular fluids, and prolonged objective regression of tumor was seen. Systemic high-dose Ara-C deserves consideration for the treatment of ocular lymphoma.