Normalization of stress and delayed thallium-201 myocardial SPECT: where is the normal reference area?

We describe an unusual uptake pattern in a thallium SPECT study performed after dipyridamole infusion in a patient with a documented history of prior inferior infarction and recent typical chest pain. The stress study exhibited maximum uptake in the inferior wall. The delayed study showed an inferior defect more consistent with the notion of inferior necrosis, with a maximum uptake in the anterior wall. The authors propose a pathophysiologic interpretation consistent with coronary angiography findings, based on the assumption of coronary steal suggested by the occurrence of chest pain at the end of the dipyridamole infusion. The problem of selecting myocardial normal reference area(s) necessary to normalization prior to quantitative comparison stress and delayed studies is discussed.

Lactate uptake by skeletal muscle sarcolemmal vesicles decreases after 4 wk of hindlimb unweighting in rats.

We investigated the effects of 4 wk of hypodynamia on the rate of lactate transport in skeletal muscle sarcolemmal vesicles from control and hindlimb-suspended rats. Characterization of the sarcolemmal preparations was achieved with a marker enzyme (K+-p-nitrophenylphosphatase) and measurement of 1 mM [U-14C]lactate transport activity under zero-trans conditions with or without a pH gradient or the transport inhibitor alpha-hydroxycinnamate. Preparations from the two groups were not significantly different concerning yield and purification. Based on these results, we used this model to analyze the lactate transport activity after hypodynamia by tail suspension. Hindlimb suspension caused a shift from slow to fast myosin heavy chain isoforms in soleus muscles with a 40% decrease in the citrate synthase activity (from 35.3 +/- 3.7 to 21.4 +/- 2.1 mu mol x g-1 x min-1; P < 0.05). Lactate (1 mM) uptake in vesicles from the two groups was a function of time, and the rate after hindlimb suspension was significantly decreased in the suspended compared with the control group (2.25 +/- 0.44 and 3.50 +/- 0.26 nmol x min-1 x mg protein-1, respectively; P < 0.05). These differences were not observed for a higher lactate concentration (50 mM). These results suggest that the level of physical activity plays a role in the regulation of sarcolemmal lactate transport activity implicated in the exchanges of lactate between producing and utilizing cells, organs, and tissues, which are major ways of carbohydrate energy distribution in humans and others species.

Effect of 2-chloropropionate on initial lactate uptake by rat skeletal muscle sarcolemmal vesicles.

2-Chloropropionate (2-CP) is a halogenated monocarboxylic acid generally used to decrease blood lactate concentration in various metabolic states. To investigate whether it has an inhibitory effect on sarcolemmal lactate transport, we compared the initial rate of lactate transport in sarcolemmal membrane vesicles purified from 20 male Wistar rats with and without 2-CP. Transport by these vesicles was measured as uptake of L-(+)-[U-14C]lactate under pH gradient-stimulated cis inhibition. The time courses of 1 mM L-(+)-lactate uptake into vesicles both with and without 10 mM 2-CP (L- or D-) displayed saturation kinetics. Lactate uptake values were lower with 10 mM L-2-CP and 10 mM D-2-CP in comparison to the control values. Both 10 mM L-2-CP and 10 mM D-2-CP significantly inhibited 1 mM L-(+)-lactate uptake (55.8 +/- 9.1 and 53.5 +/- 12.1%, respectively; P < 0.001), whereas a smaller inhibition was observed with a higher lactate concentration of 50 mM (40.2 +/- 11.2 and 38.7 +/- 12.4%; P < 0.001 and P < 0.05, respectively). However, a higher D-2-CP concentration (50 mM) increased the inhibition of pH-stimulated 1 mM L-(+)-lactate uptake (77.0 +/- 9.4%; P < 0.001). D-2-CP had a trans-stimulation effect on the initial rate of lactate efflux of 1 mM L-(+)-lactate compared with baseline efflux (9.5 +/- 0.8 vs. 5.1 +/- 0.4 nmol.min-1.mg protein-1; P < 0.05). 2-CP significantly inhibited the initial rate of lactate uptake in skeletal muscle sarcolemmal membrane vesicles. This result suggests that 2-CP is a nonstereoselective substrate of the lactate muscle carrier that impairs lactate transport.

Lactate transport activity in rat skeletal muscle sarcolemmal vesicles after acute exhaustive exercise.

The effect of a single bout of exhaustive exercise on muscle lactate transport capacity was studied in rat skeletal muscle sarcolemmal (SL) vesicles. Rats were assigned to a control (C) group (n = 14) or an acutely exercised (E) group (n = 20). Exercise consisted of treadmill running (25 m/min, 10% grade) to exhaustion. SL vesicles purified from C and E rats were sealed because of sensitivity to osmotic forces. The time course of 1 mM lactate uptake in zero-trans conditions showed that the equilibrium level in the E group was significantly lower than in the C group (P < 0.05). The initial rate of 1 mM lactate uptake decreased significantly from 2.44 +/- 0.22 to 1.03 +/- 0.08 nmol. min(-1). mg protein(-1) (P < 0.05) after exercise, whereas that of 50 mM lactate uptake did not differ significantly between the two groups. For 100 mM external lactate concentration ([lactate]), exhaustive exercise increased initial rates of lactate uptake (219.6 +/- 36.3 to 465.4 +/- 80.2 nmol. min(-1). mg protein(-1), P < 0.05). Although saturation kinetics were observed in the C group with a maximal transport velocity of 233 nmol. min(-1). mg protein(-1) and a Michealis-Menten constant of 24.5 mM, saturation properties were not seen after exhaustive exercise in the E group, because initial rates of lactate uptake increased linearly with external [lactate]. We conclude that a single bout of exhaustive exercise significantly modified SL lactate transport activity, resulting in a decrease in 1 mM lactate uptake and was associated with alterations in the saturable properties at [lactate] above 50 mM. These results suggest that changes in sarcolemmal lactate transport activity may alter lactate and proton exchanges after exhaustive exercise.

Effects of active recovery on plasma lactate and anaerobic power following repeated intensive exercise.

The purpose of this study was to investigate the effects of active recovery (AR) on plasma lactate concentration [La] and anaerobic power output as measured during repeated bouts of intense exercise (6 s) against increasing braking forces. Ten male subjects performed two randomly assigned exercise trials: one with a 5-min passive recovery (PR) after each exercise bout and one with a 5-min active recovery (AR) at a workload corresponding to 32% of maximal aerobic power. Blood samples were taken at rest, at the end of each exercise bout (S1) and at the 5th minute between bout-recovery (S2) for plasma lactate assay. During the tests, [La]S1 was not significantly different after AR and PR, but [La]S2 was significantly lower after AR for power outputs obtained at braking forces 6 kg (5.66 +/- 0.38 vs 7.56 +/- 0.51 mmol.l-1) and peak anaerobic power (PAnP) (6.73 +/- 0.61 vs 8.54 +/- 0.89 mmol.l-1). Power outputs obtained at 2 and 4 kg did not differ after AR and PR. However, when compared with PR, AR induced a significant increase in both power outputs at 6 kg (842 +/- 35 vs 798 +/- 33 W) and PAnP (945 +/- 56 vs 883 +/- 58 W). These results showed that AR between bouts of intensive exercise decreased blood lactate concentration at high braking forces. This decrease was accompanied by higher anaerobic power outputs at these forces.

Effect of NaHCO3 on lactate kinetics in forearm muscles during leg exercise in man.

We investigated NaHCO3 infusion effects on plasma lactate removal by forearm muscles and performance during intensive leg exercise. Seven subjects performed the force-velocity (FV) test with placebo and NaHCO3 (2 mEq.min-1) with a double-blind crossover protocol. Blood samples for arterial ([LA]A) and venous ([LA]V) lactate determinations were taken 1) at rest before infusion, and 2, 6, 10, 14, 18, and 22 min following its start; and 2) at the end of each exercise bout. The arteriovenous difference ([LA]A-V) was determined for each sampling. NaHCO3 significantly increased arterial bicarbonate concentration and pH during rest (P < 0.001; P < 0.001) and the FV test (P < 0.001; P < 0.05). During the test, [LA]A and [LA]V were significantly higher with NaHCO3 (P < 0.05, P < 0.001). At test onset, [LA]A-V became positive and increased until the braking force of 6 kg, with NaHCO3 and placebo, with values significantly lower for NaHCO3 (P < 0.001). Peak anaerobic power (Wanae, peak) and the corresponding braking force (Fmax) were also determined. Fmax was significantly increased with NaHCO3 (P < 0.001). In conclusion, the increasing rise in [LA]A and [LA]V induced by NaHCO3 may be partly explained by a decreased rate of lactate uptake by forearm skeletal muscles. NaHCO3 did not improve Wanae, peak, but improved Fmax, thus increasing FV duration.

[Study of left ventricular diastolic function using pulsed Doppler in myocardial infarct in hypertensive subjects]. / Etude de la fonction ventriculaire gauche diastolique par doppler pulsé dans l'infarctus du myocarde chez l'hypertendu.

To determine if impairment of left ventricular filling is influenced by acute myocardial infarction in patients with arterial hypertension, left ventricular diastolic function was assessed by pulsed doppler echocardiography in 46 patients (pts) subdivided into four groups (Gr): G.1 (n = 12 pts) with acute myocardial infarction and hypertensive heart disease. G.2 (n = 12 pts) acute myocardial infarction without arterial hypertension. G.3 (n = 10 pts) arterial hypertension without history of coronary artery disease. G.4 (n = 12 pts) healthy subjects. Coronary angiography and left ventricular cineangiogram was performed in 24 pts (G.1 + G.2). Peak mitral flow velocity (cm/s) in early diastole (E), atrial systole (A), A/E and int A/int E ratios were measured by pulsed doppler. Age and heart rate were statistically similar in all groups. No difference was found among G.1 and G.2 in ejection fraction, and left ventricular segmental kinetic. (tables; see text) Conclusion left ventricular filling is impaired in pts with arterial hypertension and in pts with acute myocardial infarction; acute myocardial infarction increase the impairment of left ventricular diastolic function in pts with hypertensive heart disease.

[Toxocariasis and functional intestinal disorders. Presentation of 4 cases]. / Toxocarose et troubles fonctionnels intestinaux. Présentation de 4 cas.

We report 4 cases of adults patients, suffering from irritable bowel syndrome, which had been attributed late to toxocariasis and for whom the treatment led to recovery. Hypereosinophilia was present only in 3 cases. These cases show that toxocariasis is not limited anymore to its two classical expressions: visceral larva migrans and ocular toxocariasis. So it is useful to think of it to confirm and treat it in the case of patients suffering from irritable bowel syndrome. This enables shorter diagnosis delay (14 months in average for our patients) and this is essential for therapeutic efficiency.

[Portable ultrasonographic device and bladder dysfunction management in stroke patients]. / Place d'un échographe vésical portable dans la prise en charge des troubles de la vidange vésicale après accident vasculaire cérébral.

OBJECTIVE: To determine the usefulness of a portable ultrasonographic device in the management and rehabilitation of stroke patients' bladder voiding impairment in the early stage and to propose a well-fitted screening protocol. MATERIAL AND METHOD: A prospective observational study of 33 inpatients admitted into our stroke rehabilitation program. A urinary elimination assessment protocol defines the criteria of intermittent catheterization. The determination of bladder volume was performed with a Bladderscan BVI 3000 portable ultrasonographic device. RESULTS: Urinary retention was present in ten of the 33 patients at admission, who were started on one or many intermittent catheterizations. Retention was resolved for seven of them at discharge. The portable ultrasonographic device allows a very accurate bladder volume assessment, especially useful in at-risk patients: those with cognitive impairments, diabetes mellitus, and prestroke urinary pathology. A new version of our first screening protocol increases the ability to detect patients with true urinary retention. Results are discussed according to the literature data. CONCLUSION: The portable ultrasonographic device is a simple and noninvasive tool, useful for diagnosis, follow-up and therapy guidance of urinary retention after stroke. An adapted protocol is proposed in order to assess and rehabilitate this trouble. The goal is to avoid long-term catheterization and its linked infectious risk.

[Hemodynamic and hormonal study of electronarcosis and neuroleptanalgesia. Clinical study in 17 surgical patients]. / Etude hémodynamique et hormonale de l'anesthésie électro-médicamenteuse et de la neuroleptanalgésie. Travail clinique chez 17 opérés.

The blocking effect of electropharmaceutical anesthesia (EPA) and neuroleptanalgesia (NLA) on adrenergic and hormonal reactions to abdominal surgery were compared in 17 ASA class I to III randomized patients. This study was intended to define the indications for each of these techniques in patients with heart diseases. Each individual received the same anesthetic premedication and induction and was submitted to iterative identical measurements and biological dosages. Before and during surgery, both groups were catheterized with a Swan-Ganz and a radial catheter. Blood sampling for catecholamines, cortisol, glycemia, blood gases dosages were regularly drawn. Electrical stimulation was performed in the EPA group, and fentanyl injections were repeated in the NLA group patients only. The same doses of pancuronium and droperidol were given to every patient. A circulatory hyperkinesia and hyperadrenergia were observed during surgery in all of the subjects but, during EPA, the tachycardia, the cardiac index and the rate-pressure product were higher than during NLA. The body temperature increased towards normal in EPA, not in NLA. Adrenergic and hormonal levels were equal in both groups. The slow variations of all the important parameters demonstrate that the measured phenomenons have a long time-course what legitimates this kind of prolonged on-the-spot observation. The role of droperidol, pancuronium and fentanyl in the observed variations is discussed. The characteristic high hyperkinesia in EPA may be due partly to an inefficacious analgesia because of the fentanyl suppression after induction, partly to the preserved thermogenesis partly to a direct effect of the electrical stimulation on cerebral tissues.

Correlations between M-mode markers of left ventricular hypertrophy and radionuclide angiographic indices of left ventricular diastolic function in mild to moderate hypertension.

This study was undertaken to determine the correlations between left ventricular hypertrophy and left ventricular diastolic function in mild to moderate essential hypertension. M-mode echocardiography and rest equilibrium radionuclide angiography were performed in 53 hypertensive subjects. The following M-mode echocardiographic parameters were measured: interventricular septal thickness, posterior wall thickness, left ventricular mass index, left atrial diameter and relative wall thickness. The following radionuclide angiography parameters were measured: ejection fraction, peak filling rate, time to peak filling rate, first third filling fraction and atrial contribution to total filling. Weak correlations were shown between left ventricular diastolic function and the M-mode echocardiographic parameters. The peak filling rate was negatively correlated with the interventricular septal thickness (r = -0.345; P less than 0.05), with the sum of the interventricular septal thickness and the posterior wall thickness (r = -0.395; P less than 0.01), with the left atrial diameter (r = -0.345; P less than 0.05), and with the relative wall thickness (r = -0.297; P less than 0.05). The time to peak filling rate was positively correlated with the left ventricular mass index (r = + 0.310; P less than 0.05) and with the left atrial diameter (r = + 0.323; P less than 0.05). These findings suggest that diastolic abnormalities in hypertensive heart disease are only in part related to the degree of left ventricular hypertrophy.

[Semi-quantitative analysis of 3-phase bone scintigraphy data in algodystrophy of the limbs]. / Analyse semi-quantitative des données de la scintigraphie osseuse en trois temps dans l'algodystrophie des extrémités.

Three-phase bone scanning of the extremities (foot or hand) was performed in 40 normal subjects and in 56 patients with an unequivocal clinical diagnosis of reflex sympathetic dystrophy. Ten patients were in the "cold" or atrophic stage of the disease process, whereas 46 were in the "hot" or acute phase. The scintigraphic parameters studied were the ratios of tracer activity in the affected side over the healthy side established for blood flow (BF), blood pool (BP), early vasculo-tissular fixation (EF), and late bone fixation (LF). In the controls, blood flow, blood pool, and early fixation showed considerable interindividual variation and only the variation of late fixation remained within narrow limits. Among the patients, those at the hot stage of the disease had significantly higher values for all four parameters than those at the cold stage. The group at the cold stage did not differ from the controls except for a significantly higher late fixation value. Furthermore, among hot stage patients, 15% to 25% had normal or diminished blood flow, blood pool and early fixation values. At the cold stage of the disease, radionuclide parameters were similar in affected feet and hands, whereas at the hot stage values at the feet were double those at the hands. Finally, statistical analysis revealed that late fixation was most closely correlated with early fixation, which in turn was most close correlated with blood pool. The clinical and pathophysiological significance of these data is discussed.

[Coverage of post-traumatic brain exposure by a total temporal flap: a case report]. / Couverture d'une exposition cérébrale post-traumatique par un lambeau temporal total : à propos d'un cas.

Major defect of the scalp associated with penetrating brain injury is one of the most challenging issues in acute craniofacial trauma. Depressed skull fractures associated with injuries of the skin and periosteal tissue can be easily covered using various locoregional scalp flap techniques. However, if the skin is damaged around the wound, the surgical possibilities are reduced, allowing only local transposition flap or free flap coverage with many disadvantages for the latter such as vascular micro-anastomosis issues, unsuitable underlying vascular status, and a "patch" effect which is often unsightly. The authors describe, using a clinical case, the steps to provide a total temporal flap to cover a defect of both skin and bone. This can be performed in three separated stages: the first is the empowerment of both middle temporal pedicles; the second stage, 15 days later, is the section, transposition and coverage of the wound; the third stage, 30 days later, is the flap separation.

[Vascularized bone transfer of scapula apophysis]. / Transfert osseux vascularisé d'épiphyse scapulaire.

The vascularized bone transfer of the scapular apophysis was described for the first time by Gilbert and Téot (1982) [1]. The growing pattern of this specific apophysis has large capacity and the plasticity during remodeling is unique. Primarily used for mandibular reconstruction, the scapular crest is also suitable for humeral or femoral reconstruction as well as for carpal stabilization in radial hand malformation, which is considered to be the main clinical indication. The radial hand malformation is characterized by an insufficient ulnar carpal stabilization which leads to luxation and radial deviation of the carpus. Using the vascularized scapular transfer in volar apposition to the ulnar, it enables enlarging the contact surface area with the carpus, thus stabilizing the wrist. Due to the preserved epiphyseal vascularization, good remodeling and integration of the scapular crest is achieved until consolidation takes place.