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Lamellarins are natural products with a [3,4]-fused pyrrolocoumarin skeleton possessing interesting biological properties. More than 70 members have been isolated from diverse marine organisms, such as sponges, ascidians, mollusks, and tunicates. There is a continuous interest in the synthesis of these compounds. In this review, the synthetic strategies for the synthesis of the title compounds are presented along with their biological properties. Three routes are followed for the synthesis of lamellarins. Initially, pyrrole derivatives are the starting or intermediate compounds, and then they are fused to isoquinoline or a coumarin moiety. Second, isoquinoline is the starting compound fused to an indole moiety. In the last route, coumarins are the starting compounds, which are fused to a pyrrole moiety and an isoquinoline scaffold. The synthesis of isolamellarins, azacoumestans, isoazacoumestans, and analogues is also described. The above synthesis is achieved via metal-catalyzed cross-coupling, [3 + 2] cycloaddition, substitution, and lactonization reactions. The title compounds exhibit cytotoxic, multidrug resistance (MDR), topoisomerase I-targeted antitumor, anti-HIV, antiproliferative, anti-neurodegenerative disease, and anti-inflammatory activities.

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Pyridocoumarins are a class of synthetic and naturally occurring organic compounds with interesting biological activities. This review focuses on the synthetic strategies for the synthesis of pyridocoumarins and presents the biological properties of those compounds. The synthesis involves the formation of the pyridine ring, at first, from a coumarin derivative, such as aminocoumarins, hydroxycoumarins, or other coumarins. The formation of a pyranone moiety follows from an existing pyridine or piperidine or phenol derivative. For the above syntheses, [4 + 2] cycloaddition reactions, multi-component reactions (MCR), as well as metal-catalyzed reactions, are useful. Pyridocoumarins present anti-cancer, anti-HIV, antimalarial, analgesic, antidiabetic, antibacterial, antifungal, anti-inflammatory, and antioxidant activities.

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Twenty-four patients with moderate or severe valvular pulmonary stenosis were treated by percutaneous transluminal valvuloplasty (PTV). The age of the patients ranged from 24 hours to 27 years. Eighteen patients (group I) had a right ventricle-pulmonary artery (RV-PA) pressure gradient greater than 50 mmHg (measured simultaneously or during catheter withdrawal). Six patients (group II) had RV-PA pre-sure gradients of less than 50 mmHg. Twenty-seven PTV procedures were performed. Six of the 24 patients were under 2 months of age, including 4 who were less than 1 week old. The youngest patient (under 24 hours old) had valvular pulmonary stenosis, very nearly atresia. PTV was carried out using Rashkind's technique on 2 occasions and with a dilatation catheter with a balloon of 6 to 20 mm of diameter on the other 25 occasions. In 6 cases, 2 dilatation catheters were introduced and inflated simultaneously in the pulmonary valve. The overall results were satisfactory: RV pressure fell from 87.6 to 54.4 mmHg, the RV-PA gradient from 72.3 to 31.9 mmHg and the ratio of RV/systemic pressure from 104.4 to 51.1. The improvement was more marked in group I than in group II. The causes of failure are discussed: valvular dysplasia, severe infundibular hypertrophy, inadequate diameter of the balloon. Tolerance of PTV was very good. The value of this procedure is emphasised. It may save surgical valvotomy in high risk groups of patients, such as the newborn and infants. The haemodynamic results of PTV are maintained at long-term, but the number of cases is still too small.

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Fifty-nine patients operated for Fallot's tetralogy were reviewed over 3 years after surgery. The average age at surgery was 7.4 years (range 6 months to 37 years). The review included ECG, chest X-ray, echocardiography, exercise stress testing and Holter monitoring, completed by cardiac catheterisation in 10 cases and electrophysiological investigation in 4 cases. Forty-eight of the 59 patients (81.3 p. 100) had no signs of ventricular arrhythmia or only benign ventricular extrasystoles (Group I). Four patients (6.8 p. 100) had severe ventricular arrhythmias (Group II). Seven patients (11.9 p. 100) had one or more episodes of ventricular tachycardia (VT) (Group III) and, in 3 of these patients, VT was recorded during Holter monitoring or exercise stress testing. One patient in Group III died after reoperation, but there were no cases of sudden death in this series. The high risk patients Groups II and III) were operated late (after 5 years), had bi- or trifascicular block (7 out of 11 cases), ventricular extrasystoles on resting ECGs (9 out of 11 cases), cardiomegaly (6 out of 7 cases in Group III), echocardiographic dilatation of the infundibulum (6 out of the 8 patients undergoing echocardiography in Groups II and III). They had significant residual malformation but without right ventricular hypertension (as judged mainly by immediate postoperative data). Ventricular arrhythmias occurred over 6 years after surgery. However, none of the patients operated before 2 years of age had ventricular arrhythmias or VT with a mean follow-up period of 7.5 years, perhaps because LV function was protected.(ABSTRACT TRUNCATED AT 250 WORDS)

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Abnormal atrioventricular conduction in children and adolescents without obvious underlying cardiac disease poses the problem of long term prognosis. This study of 45 patients aged 8 to 18 years with congenital atrioventricular block (30 cases) or ventricular pre-excitation (15 cases), was undertaken to determine the value of exercise testing, a physiological adrenergic stress test, in the assessment of these patients. Our results show that exercise testing was valuable in determining the site of atrioventricular block: during exercise the degree of block increased in two patients, justifying electrophysiological investigations which showed infrahisian block in one case; when the block was stable or improved on exercise, the atropine test, performed in 21 cases, gave concordant results in 18 cases (the same change with atropine and exercise): the block was nodal in all these patients. A concordant response to exercise and atropine, improving the degree of block, indicates suprahisian block and endocavitary investigation would not seem to be necessary. On the other hand, when the degree of block increases or remains the same during exercise and/or the atropine test, the site of block cannot be predicted and endocavitary investigation and Holter monitoring may be required. In patients with ventricular pre-excitation, exercise testing provides information on the relative values of the effective refractory periods of the normal and accessory pathways: in the 10 cases in which endocavitary studies were undertaken, the exercise electrocardiogram changed in the expected manner (disappearance of the pre-excitation wave on exercise in patients with accessory pathways with longer refractory periods than the normal pathway and persistence of pre-excitation when the accessory pathway refractory period was shorter).(ABSTRACT TRUNCATED AT 250 WORDS)

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Echocardiographic assessment of cardiac function was made on 24 children with chronic renal failure of varying etiology and severity. In 20 patients without evidence of cardiac failure, parameters of left ventricular performance as represented by PEP/LVET and mean velocity of circumferential fiber shortening were within normal limits in the majority of patients. In addition, ejection fraction and shortening fraction were, in most children, within the 95% confidence limits for their age. In 4 patients who presented with congestive heart failure, marked left ventricular dilatation was noted in association with decreased shortening and ejection fractions and depressed mean velocity of circumferential fiber shortening. Also the PEP/LVET in these patients suggested the presence of a uremic cardiomyopathic condition. These studies, in addition to our own studies on children who have undergone fistula construction, hemodialysis, and transplantation, suggest that cardiac performance, in the majority of pediatric patients with end-stage renal disease, is well maintained and that the major factor involved in reducing exercise tolerance is the presence of uremic anemia. Only a minority of patients may develop severe uremic heart disease.

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Based on data from the literature and their own experience, the authors study the long-term clinical course of patients with interatrial communications (IAC), coarctation of the aorta (CAo) and tetralogy of Fallot (TF) who have been operated. According to data from the literature and 50 cases which were reviewed an average of 11 years after the operation, operated cases of IAC are at risk of developing arrhythmias or conduction disturbances, especially if the operation was performed after the age of 20, in cases with cardiomegaly, with a mean pulmonary artery pressure of more than 20 mmHg and a pulmonary flow/systemic flow ratio due to the shunt greater than 1.5. Surgery for CAo carries a risk of long-term residual hypertension (HT). According to the majority of authors and a study of 55 cases. HT is present in 3 to 6% of cases operated between the ages of 1 and 10 years. This percentage is much higher for the older age groups. The increase in blood pressure on effort and the demonstration of a gradient between the upper limb and the lower limb are the methods of detecting post-operative hypertension and residual stenosis. Cardiac failure and coronary occlusion can occur in the cases which were operated late. Following complete correction of TF, severe ventricular arrhythmias can arise in the long term. From a study of 59 patients at least 3 years after the operation, the authors outline the elements which favour the development of these arrhythmias. The cases at highest risk are those which were operated after the age of 2 years with significant residual lesions, cardiomegaly and ventricular extrasystoles on the resting trace.(ABSTRACT TRUNCATED AT 250 WORDS)

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The echocardiographic features of 14 patients with double-chambered right ventricle are presented. Diagnosis was confirmed in 13 patients at cardiac catheterization and in one at necropsy. The ultrasonic diagnosis was based on the visualization in subxiphoid short-axis view of an anomalous muscle bundle at the lower margin of the right ventricular infundibulum; this structure was present in diastole and systole and the distal portion of infundibulum was wide and free of obstruction. Associated lesions were very frequent (especially ventricular septal defects, present in 13 patients). Subxiphoid two-dimensional echocardiography is an easy, reliable, noninvasive means of assessing this disease in infants and children.

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