Biomedical subjects

C Piot

Publications and source records attributed to C Piot.

At least 37 records · Page 2Linked to original sources

PubMed1998

Heart rate as a determinant of L-type Ca2+ channel activity: mechanisms and implication in force-frequency relation.

Early studies in enzymatically isolated animal cardiomyocytes indicated that voltage-gated "L-type" Ca2+ currents (ICaL) can be upregulated following an increase of the frequency of activation. Recently, we evidenced a similar regulation of ICaL in human cardiomyocytes from both left and right ventricles and atria over a physiopathological range of stimulations (between 0.5 and 5 Hz). This regulation, enhanced by the beta-adrenergic stimulation, may be involved in the frequency-dependent potentiation of cardiac contractile force in the human healthy myocardium. We show here that the frequency-dependent regulation of ICaL is controlled by the level of phosphorylation, as well as dephosphorylation, of the Ca2+ channels. It was enhanced following activation of the protein kinase A activated by intracellular cyclic AMP (cAMP). Therefore, we anticipate that all agents stimulating cAMP production will favor this process, which was demonstrated here by activating 5HT-4 receptors using serotonin. Alternatively, it was also enhanced by the phosphatase inhibitor okadaic acid which prevents Ca2+ channels dephosphorylation. Alteration or abnormal modulation by beta-adrenergic receptor stimulation of the frequency-dependent facilitation of ICaL may partly explain the altered force-frequency relation described in heart failure.

Biomechanical Phenomena↗

PubMed1998

Ca2+ currents in compensated hypertrophy and heart failure.

Transmembrane voltage-gated Ca2+ channels play a central role in the development and control of heart contractility which is modulated by the concentration of free cytosolic calcium ions (Ca2+). Ca2+ channels are closed at the normal membrane resting potential of cardiac cells. During the fast upstroke of the action potential (AP), they are gated into an open state by membrane depolarisation and thereby transduce the electrical signal into a chemical signal. In addition to its contribution to the AP plateau, Ca2+ influx through L-type Ca2+ channels induces a release of Ca2+ ions from the sarcoplasmic reticulum (SR) which initiates contraction. Because of their central role in excitation-contraction (E-C) coupling, L-type Ca2+ channels are a key target to regulate inotropy [1]. The role of T-type Ca2+ channels is more obscure. In addition to a putative part in the rhythmic activity of the heart, they may be implicated at early stages of development and during pathology of contractile tissues [2]. Despite therapeutic advances improving exercise tolerance and survival, congestive heart failure (HF) remains a major problem in cardiovascular medicine. It is a highly lethal disease; half of the mortality being related to ventricular failure whereas sudden death of the other patients is unexpected [3]. Although HF has diverse aetiologies, common abnormalities include hypertrophy, contractile dysfunction and alteration of electrophysiological properties contributing to low cardiac output and sudden death. A significant prolongation of the AP duration with delayed repolarisation has been observed both during compensated hypertrophy (CH) and in end-stage HF caused by dilated cardiomyopathy (Fig. 1A) [4-8]. This lengthening can result from either an increase in inward currents or a decrease in outward currents or both. A reduction of K+ currents has been demonstrated [6,9]. Prolonged Na+/Ca2+ exchange current may also be involved [9]. In contrast, there is a large variability in the results concerning Ca2+ currents (ICa). The purpose of this paper is to review results obtained in various animal models of CH and HF with special emphasis on recent studies in human cells. We focus on: (i) the pathophysiological role of T-type Ca2+ channels, present in some animal models of hypertrophy; (ii) the density and properties of L-type Ca2+ channels and alteration of major physiological regulations of these channels by heart rate and beta-adrenergic receptor stimulation; and (iii) recent advances in the molecular biology of the L-type Ca2+ channel and future directions.

Adrenergic beta-Agonists↗

PubMed1998

Contribution of mitochondria and peroxisomes to palmitate oxidation in rat and bovine tissues.

Total and peroxisomal palmitate oxidation capacities and mitochondrial enzyme activities were compared in tissues from growing rats, preruminant calves and 15-month-old bulls. Total palmitate oxidation rates were 1.9-5.2-fold higher in rat than in bovine tissues and 1.7-fold higher in the heart and muscles from calves than from growing bulls. The peroxisomal contribution to palmitate oxidation was similar between rats and bovines (i.e. calves and bulls) in liver (35-51%), heart (26%) but not in muscles (14 +/- 3% in rats vs 33 +/- 4.5% in bovines, P < 0.05). Mitochondrial enzyme activities were 1.8-4.8-fold higher in rat than in bovine tissues but the citrate synthase to cytochrome-c oxidase ratio was the highest in the liver (17-38), intermediate in the heart and muscles from calves and rats (6-10) and the lowest in heart and muscles from bulls (2-3, P < 0.05). In all tissues and animal groups, palmitate oxidation rates were similar per unit cytochrome-c oxidase activity, but not always per unit citrate synthase activity. Therefore, differences in mitochondrial contents (as between rats and bovines) or in mitochondrial characteristics (as between liver and muscles) relate to the differences in palmitate oxidation capacity.

Animals↗

PubMed1998

Developmental changes in apolipoprotein B gene expression in the liver of fetal calves.

Changes in apolipoprotein (apo B) gene expression in the liver were determined in fetal calves from 90 to 260 days of intrauterine life. Results were compared with those obtained from the livers of 1-month-old calves and adult cows. By Western blot analysis using a rabbit antiserum to bovine apo B, apo B100 was detected from 90 days of intrauterine life. Apo B100 was shown to be the only form of apo B detected in the liver of fetal calves whatever the gestational age indicating the lack of editing process during the prenatal period. Hepatic apo B contents were stable during intrauterine life and comparable to those of calves and lower than those of cows. Hepatic contents of apo B mRNA increased with the gestational age similarly to total RNA. Values of apo B mRNA at 260 days of intrauterine life were comparable to those in the liver of 1-month-old calves and adult cows. These results suggested that hepatic synthesis of calf apo B during fetal development is specifically regulated at a posttranscriptional level, either by a decrease in the rate of translation and/or by an increase in the rate of intracellular apo B degradation.

Aging↗

PubMed1997

Ceramide is involved in triggering of cardiomyocyte apoptosis induced by ischemia and reperfusion.

Involvement of ceramide signaling in the initiation of apoptosis induction in myocardial cells by in vitro and in vivo ischemia and reperfusion was analyzed. Synthetic cell permeable C2-ceramide induced apoptotic death of rat neonatal cardiomyocytes in vitro. In vitro ischemia (oxygen/serum/glucose deprivation) led to a progressive accumulation of ceramide in cardiomyocytes. After 16 hours of simulated in vitro reperfusion (readdition of oxygen, serum and glucose), the level of ceramide in surviving cells was found to have returned to baseline, whereas, levels in nonadherent dead cells remained high. In the rat heart left coronary artery occlusion model, ischemia with the subsequent reperfusion, but not ischemia alone, induced apoptosis in myocardial cells as demonstrated by DNA electrophoresis and measurement of soluble chromatin degradation products. The content of ceramide in ischemic area was elevated to 155% baseline levels at 30 minutes, and to 330% after 210 minutes of ischemia. Ischemia (30 minutes) followed by reperfusion (180 minutes) increased the ceramide level to 250% in the ischemic area. The combination of results obtained in both in vitro and animal models demonstrate for the first time that ceramide signaling can be involved in ischemia/reperfusion death of myocardial cells.

Animals↗

PubMed1996

Comparison of four methods for isolating large mRNA: apolipoprotein B mRNA in bovine and rat livers.

The effectiveness of four methods for isolating large-size mRNA (14 kb) encoding for hepatic bovine apoprotein B (apo B) was compared. Total RNA of liver (positive controls) and lung (negative controls) samples taken in bovine and rat was extracted using the methods of Chirgwin et al., Chomczynski and Sacchi, Cathala et al., and RNAzol. The integrity of total RNA extracted by the four methods was demonstrated by electrophoresis on 1% agarose gel and staining with ethidium bromide. Yield of extraction was two- to four-fold higher for all samples with the methods of Chirgwin et al. and RNAzol than that with the other methods. By dot blot analysis, apo B mRNA in bovine and rat livers was revealed preferentially with Chirgwin et al. and RNAzol methods. By Northern blot analysis, a single band corresponding to apo B100 mRNA was shown in bovine and rat livers only with the method of Chirgwin et al., whereas a band corresponding to a medium-size mRNA (2.6 kb) encoding for rat phosphoenolpyruvate carboxykinase was revealed in rat liver samples with the four methods. These results showed the favorable role of guanidium isothiocyanate and guanidium hydrochloride used in the extraction and the purification of RNA, respectively, especially in the case of high-molecular-weight and/or low-represented RNA such as apo B mRNA in bovine liver.

Animals↗

PubMed1996

High frequency-induced upregulation of human cardiac calcium currents.

BACKGROUND: In mammalian heart cells, Ca2+ influx through voltage-gated L-type Ca2+ channels can be upregulated by high rates of stimulation. We have investigated this important adaptive regulation in human cardiomyocytes. METHODS AND RESULTS: Using the whole-cell patch-clamp technique, we found a high frequency-induced upregulation (HFIUR) of the dihydropyridine-sensitive L-type Ca2+ current (ICa) in human cardiomyocytes. ICa was potentiated in a graded manner with increasing rates of stimulation between 0.3 and 5 Hz. Both moderate increase of ICa peak amplitude and marked slowing of current decay contributed to large increases of Ca2+ influx (up to 80%). The maximal potentiation of ICa was reached rapidly after the change in the rate of stimulation (no more than a few seconds). Beta-Adrenergic stimulation of the cells by isoproterenol (1 micromol/L), which is well known to induce a slow (approximately 1 minute) cAMP-mediated potentiation of ICa, could enhance (when present) or promote (when absent) the HFIUR of ICa. As a consequence, the increasing effect of isoproterenol on Ca2+ influx through Ca2+ channels was dependent on the rate of stimulation. HFIUR of ICa was altered in patients with ejection fraction lower than 40% and in patients pretreated with Ca2+ antagonists or beta-blockers. CONCLUSIONS: Upregulation of Ca2+ entry through voltage-gated Ca2+ channels by high rates of beating may be involved in the frequency-dependent regulation of contractility (Bowditch "staircase") of the human heart. This process, which is highly sensitive to beta-adrenergic stimulation, may be crucial in adaptation to exercise and stress.

Adult↗

PubMed1996

[Thrombosis from mechanical valve prostheses in the Reunion island].

Between October 1991 and January 1995, 10 patients presented 14 episodes of thrombosis of mechanical valve prosthesis, 11 obstructive, 3 nonobstructive. In two cases, the thrombosis was recurrent (one after thrombolysis, one after surgical thrombectomy). In another two cases, the thrombosis was a recurrence (on a valve already surgically replaced because of thrombosis). Anticoagulant therapy had been ineffective in 9 cases; protein S deficiency was diagnosed in one case. Transoesophageal echography allowed diagnoses in all cases. Thrombolysis was the treatment of first intention in 9 cases (completed by a second course of thrombolysis in one case and by valvular replacement in two cases. The other patients were managed by immediate valve replacement in two cases, thrombectomy in one case, long-term parenteral anticoagulation in two cases (one of which was followed by valve replacement). Transoesophageal echography showed improved valve motion. Incomplete thrombus dissolution was observed in 50% of cases. Thrombolytic therapy was complicated by cerebrovascular accidents in two patients, one of which was fatal. One patient had regressive hemiplegia, one patient had a local hematoma. The authors conclude that thrombosis is a serious complication of valve replacement and usually occurs in patients inadequately anticoagulated. Thrombolysis may enable some patients to avoid reoperation but its risks limits its use to those patients thought to be unacceptable surgical risks. An apparently high frequency of this complication durind this period has led to the initiation of a study to determine the predisposing factors and to put preventive measures into action.

Adult↗

PubMed1995

Tetrodotoxin-sensitive Ca2+ and Ba2+ currents in human atrial cells.

A tetrodotoxin (TTX)-sensitive fast inward Ca2+ current (ICa,TTX) was recorded at physiological Ca2+ levels (2 mM) in human single atrial cells. The whole-cell patch-clamp method and Na(+)-free solutions (20-22 degrees C) were used. ICa,TTX depended upon extracellular Ca2+. It was prominent at rather negative test potentials (maximal peak amplitude at approximately -40 mV) and was observed only at holding potentials lower than -80 mV. It had the same size and kinetics when Ca2+ was exchanged for Ba2+ as the charge carrier. Its rapid activation and inactivation kinetics, voltage-dependent availability and fast recovery from inactivation resembled that of the Na+ currents (INa). ICa,TTX was insensitive to 250 microM Ni2+ and 10 microM La3+, both known to block totally T-type ICa (not evidenced here). ICa,TTX was suppressed by Na+ channel inhibitors such as TTX (10 microM) and Cd2+ (20 microM) and its decay was slowed by the specific Na+ channel activator veratrine (200 micrograms/ml). We found that both time to peak and time-constant of inactivation of ICa,TTX were slower than that of INa. There was no correlation between the presence and size of ICa,TTX and that of INa. In conclusion, ICa,TTX may reflect the presence and activation of either Ca(2+)-conducting channels related to Na+ channels or, alternatively, of a fraction of Na+ channels with an increased permeability for Ca2+ and Ba2+ ions.

Atrial Function↗

PubMed1994

Regulation of the frequency-dependent facilitation of L-type Ca2+ currents in rat ventricular myocytes.

1. An increase in the rate of stimulation induces an augmentation of L-type Ca2+ currents (ICa) and concomitant slowing of current decay in rat ventricular cells. This facilitation is quasi immediate (1-3 s), graded with the rate of stimulation, and occurs only from negative holding potentials. We investigated this effect using trains of stimulation at 1 Hz and the whole-cell patch-clamp technique (18-22 degrees C). 2. The decay of ICa is normally bi-exponential and comprises fast and slow current components (ICa,fc and ICa,sc, respectively). Facilitation of ICa was observed only when ICa,fc was predominant. 3. Facilitation developed during the run-up of ICa with the interconversion of ICa,sc into ICa,fc, and vanished during the run-down of ICa with the loss of ICa,fc.Ni2+ (300 microM) and nifedipine (1 microM) suppressed facilitation owing to the preferential inhibition of ICa,fc. 4. Facilitation of ICa was not altered (when present) or favoured (when absent) by the cAMP-dependent phosphorylation of Ca2+ channels promoted by isoprenaline or by intracellular application of cAMP or of the catalytic subunit of protein kinase A (C-sub). A similar effect was observed when the dihydropyridine agonist Bay K 8644 was applied. In both cases, facilitation was linked to a preferential increase of ICa,fc. 5. Following intracellular application of inhibitors of protein kinase A in combination with a non-hydrolysable ATP analogue, ICa consisted predominantly of ICa,sc and no facilitation was observed. The calmodulin antagonist naphthalenesulphonamide had no effect on facilitation. 6. When Bay K 8644 was applied in combination with isoprenaline, cAMP or C-sub, the decay of ICa was slowed with the predominant development of ICa,sc, and facilitation of ICa was nearly abolished. Facilitation also depended on extracellular Ca2+, and was suppressed when Ba2+ replaced Ca2+ as the permeating ion. 7. When no EGTA was included in the patch pipette, facilitation was not further enhanced but a use-dependent decrease of ICa frequently occurred. When BAPTA was used in place of EGTA, the rate of inactivation of ICa was reduced and facilitation was abolished. 8. In conclusion, the facilitation of ICa that reflects a voltage-driven interconversion of ICa,fc into ICa,sc is also regulated by Ca2+ and by cAMP-dependent phosphorylation. The presence of the gating pattern typified by ICa,fc is required. Ca2+ may exert its effect near the inner pore of the Ca2+ channel protein and control the distribution between the closed states of the two gating pathways.

Animals↗

PubMed1991

[Lung resection for cancer in coronary patients. Immediate and medium-term results. Retrospective study in a series of 51 patients].

Patients with both resectable lung cancer and coronary artery disease require preoperative cardiac evaluation in order to determine and prevent the surgical risk and to discuss the desirability of preventive myocardial revascularization. The results of thoracic surgery in coronary disease patients have been studied in a series of 51 patients operated upon for lung cancer at the Marie Lannelongue hospital, Paris, between 1985 and 1988. Thirty-two patients underwent non invasive exploration prior to surgery (exertion ECG in 22, myocardial radioisotope scanning in 10); 35 patients had coronary arteriography at the last moment, and 9 asymptomatic patients with an old history of myocardial infarction had no specific exploration. Forty-nine patients had lung surgery alone, preceded in 5 cases by percutaneous coronary angioplasty; one patient had pulmonary surgery and coronary surgery simultaneously, and another patient had coronary surgery first, later followed by lung surgery. No perioperative death was due to cardiovascular causes. A 75-year old male patient died of respiratory failure 30 days after lobectomy. The postoperative period was totally uneventful in 39 patients. No perioperative myocardial infarction was recorded; 4 patients experienced an episode of thoracic pain with ECG signs of myocardial infarction but no rise in serum enzyme concentrations. One patient had a cerebral vascular accident responsible for hemiplegia. Two late sudden deaths, probably of cardiac origin, occurred 4 and 11 months respectively after surgery. The actuarial survival rate at 3 months was 48 percent. In all survivors, the coronary symptoms were controlled by medical treatment. It seems, therefore, that perioperative complications in this type of patient can be avoided by preoperative evaluation of the coronary disease and by preventive myocardial revascularization in case of critical coronary stenosis.

Adenocarcinoma↗

PubMed1991

[Endoluminal occlusion, using a catheter, of patent ductus arteriosus in an adult].

The risk of surgical closure of the ductus arteriosus in the adult is greater than in children. The ductus arteriosus can now be occluded by venous catheterisation using a Rashkind umbrella. This procedure vas performed in a 63 year old woman. The diagnosis was confirmed and the anatomy of the lesion defined by catheterisation with aortography. The patent ductus was then occluded with a balloon catheter to assess the reversibility of the pulmonary hypertension. A 17 mm Rashkind umbrella was then used to completely occlude the ductus. The advantages of the method over surgical closure are: absence of morbidity related to thoracotomy, to general anaesthesia, to blood transfusion and the reduction of hospital stay to 3 days.

Cardiac Catheterization↗

PubMed1985

[Malformations of the tricuspid valve associated with Fallot's tetralogy. Apropos of a series of 224 surgically treated Fallot's tetralogies].

This study was based on 7 children aged 20 months to 13 years with tetralogy of fallot (TOF) and tricuspid valve defects. Cases of endocardial cushion defects (8 cases of atrioventricular) were excluded. Three types of tricuspid valve defect were observed: 4 tricuspid valve prolapse (with one associated mitral valve prolapse); 2 accessory tricuspid valves passing through a ventricular septal defect to prolapse in diastole under the aortic valve; 1 Ebstein anomaly. The prevalence of tricuspid valve defects associated with TOF 3 p. 100 in this series. The diagnosis can: usually be made by 2D echocardiography. Tricuspid valve prolapse (usually the septal leaflet) is visualised in the apical 4 chamber view. The passage of accessory tricuspid tissue across the VSD into the left ventricular outflow tract is visible in the parasternal long axis or subcostal long axis views. Ebstein anomaly can be demonstrated in apical 4-chamber views showing the abnormally apical site of insertion of the septal leaflet of the tricuspid valve and "atrialisation" of part of the right ventricle. Tricuspid valve defects did not pose any special surgical problems during complete repair of TOF but this series did not include any cases of tricuspid hypoplasia or parachute tricuspid valve which have been reported in the literature and which do complicate surgery. Tricuspid valve and subendocardial cushion defects should be looked for systematically in patients with TOF undergoing 2D echocardiography.

Adolescent↗

PubMed1983

[2-dimensional contrast echocardiographic diagnosis of associated atrioventricular canal and cor triatriatum].

2D echocardiography provided the diagnosis of partial atrioventricular canal associated with cor triatriatum in a 4 year old child. The apical four chamber view showed an ostium primum and the presence of an abnormal transverse echo in the left atrium, dividing it into ventral and dorsal chambers. Contrast echocardiography in the four chamber apical view showed an atrial right to left shunt and only opacification of the ventral chamber of the left atrium at the mitral orifice. On the other hand, the dorsal chamber which received the pulmonary veins could not be opacified by contrast. The contrast injection allowed the diagnosis to be confirmed by demonstrating the division of the left atrium into two chambers.

Child, Preschool↗

PubMed1983

[Pacemakers in infants and young children. Comparative study of pleural and lumbar modes of implantation].

The authors report their experience of 62 implantations of pacemakers in babies and small children by two different methods. The pleural cavity was chosen as the site of implantation in 22 patients aged 8 months to 10 years, weighing 4,2 to 26 kg, with a maximum follow-up period of 7 years. Reoperation was required in 11 cases: 6 replacements of mercury batteries, 5 electrode dysfunctions, 1 electrical leak syndrome and 1 septic complication. In the other 40 patients aged 24 hours to 17 years, weighing 2,2 to 37 kg, with a maximum follow-up period of 5 years, the pacemaker was implanted in the lumbar region. Reoperation was required in 4 cases; 1 pacemaker replacement for infection and 3 electrode faults with pacemaker replacement. It is 5 years since the authors abandoned the pleural cavity in favour of the lumbar area as the site of implantation in babies and small children. Programmable pacemakers with lithium power sources are preferred for their many well known advantages. The use of the pulse generators and the progressive improvement in the electromechanical properties of the pacing electrodes which have become more and more reliable, have made reoperation a rare occurrence. In addition, replacement of implanted material only requires a small lobotomy in the great majority of cases. Recurrent thoracotomies, difficult for the surgeon and dangerous to the patient, are thereby avoided.

Adolescent↗

PubMed1982

[Two-dimensional echocardiography in subvalvular aortic stenosis. Apropos of 20 cases].

Twenty cases of discrete subvalvular aortic stenosis in children aged from 8 months to 23 years were examined by 2-dimensional echocardiography and cineangiography. Fifteen of these patients subsequently underwent open heart surgery to relieve the obstruction. In 18 cases the obstacle was a fixed stenosis (13 type I, 3 type II and 2 type III) and in two cases, the obstacle was provoked by accessory tissues of the anterior mitral leaflet. The echocardiographic incidences used were the left parasternal long axis, the apical LAO-equivalent, and longitudinal and transverse subcostal views. In type I, fixed subvalvular stenosis, one fine abnormal echo was visualised in the left ventricular outflow tract throughout the cardiac cycle immediately below the aortic valve, best seen on apical views. Twelve of the 13 stenoses of this type were demonstrated by 2D echocardiography. In type II stenosis an abnormal thickened echo was visualised in the left ventricular outflow tract at a distance from the aortic cups. The adherence of this abnormal echo to the anterior mitral leaflet was best demonstrated by apical views. All three cases of this type were demonstrated by echocardiography. Type III stenosis was characterised by widespread narrowing of the subaortic region with irregular borders. Obstruction due to accessory tissues of the anterior mitral leaflet were well demonstrated in left parasternal long axis and apical views. They showed an even rounded mass of echos attached to the anterior aspect of the anterior leaflet prolapsing into the left ventricular outflow tract. Both cases in this series were diagnosed by 2D echocardiography. Therefore, 2D echocardiography with apical and subcostal views is a valuable method for diagnosing subvalvular aortic stenosis and for determining its anatomical type.

Adolescent↗

PubMed1981

[Diagnosis and localization of ventricular septal defects by two-dimensional echocardiography. 50 cases].

A series of 50 children aged between 1 month and 15 years old, with ventricular septal defects (VSD) were investigated by two-dimensional sector scanning and cineangiography. Fifty other children of the same age group with congenital heart disease without VSD were also investigated by two-dimensional echocardiography and angiography. No VSDs were diagnosed by echocardiography in children with angiographically intact inter ventricular septa. In the group with VSD, two-dimensional echo localised with precision: --36 membranous VSDs (36/36) --5 infundibular VSDs (5/6) --2 isolated muscular VSDs (2/2) --I atrioventricular canal type VAD (I/I) --3 multiple VSDs (3/5). The subcostal view was the most useful for visualising the VSD in 49 out of 50 cases. The parasternal views only showed the VSD in 23 cases, and the apical views only in II cases. The dimensions of the left heart chambers and the movement of the interatrial septum gave an indication of the volume of the left-to-right shunt. Dilatation of the left heart chambers and bowing of the interatrial septum into the right atrium in systole were observed in all cases where QP/QS greater than 2, except when there was an associated atrial septal defect. Two-dimensional echo also detected associated lesions: pulmonary stenosis (9/9), prolapse of an aortic valve cusp (4/5), atrial septal defect (2/2), stradling of the tricuspid valve (I/2). Two-dimensional echocardiographic short axis subcostal views are reliable in the detection and localisation of VSD. Nevertheless, trabecular and apical VSDs are particularly difficult to visualise and the use of pulsed Doppler coupled with two-dimensional echocardiography should enhance the sensitivity in diagnosing this type of VSD.

Adolescent↗

PubMed1981

[Diagnosis of a complete atrioventricular canal with infundibular pulmonary stenosis and left superior vena cava by 2-dimensional contrast echocardiography. Apropos of a surgically treated case].

The case of an eight year old child with complete atrioventricular canal, pulmonary infundibular stenosis and persistent left superior vena cava draining into the coronary sinus is reported. Two-dimensional echocardiography with injection of contrast in a left arm vein gave a precise and complete diagnosis of the malformations before catheterisation and angiography. The complete atrioventricular canal was demonstrated by apical four-chamber views. The pulmonary infundibular stenosis was visualised by a short axis subcostal view. Contrast echocardiography in the apical four-chamber view showed a right-to-left shunt at atrial level at the site of the ostium primum and a right-to-left shunt at ventricular level just below the hemivalve. The left superior vena cava was detected by a short axis suprasternal view which visualised its vertical trajectory as far as the coronary sinus. The lesions were confirmed at surgery, and a complete repair was performed.

Atrioventricular Node↗