[Primary pulmonary hypertension in pregnancy--a case report]. / Pierwotne nadcisnienie plucne w ciazy--opis przypadku.

Primary pulmonary arterial hypertension, so called idiopathic pulmonary arterial hypertension (IPAH), is a rare and progressive disease with poor prognosis. Pregnancy in patients with this condition is hazardous and makes the prognosis significantly worse. According to WHO, IPAH is a contraindication to pregnancy because of high risk of maternal death and WHO advises to discuss termination in the event of pregnancy Below we describe a case of a young woman at 16 weeks pregnancy with severe decompensated primary pulmonary hypertension. The patient was admitted to our department because of increasing dyspnoea and swollen legs occurring from 14th week of pregnancy. In the past the patient had been diagnosed with pulmonary hypertension, which had been defined during differential diagnostics as primary pulmonary hypertension. Echocardiographic examination over the last 4 years revealed stable mean pulmonary artery pressure (PAP) of about 50 mmHg. The patient was treated efficiently with sildenafil for the last 2 years, but the therapy was discontinued after finding pregnancy. On admission it was established that pregnancy should be terminated. Other reasons of circulatory decompensation, such as pulmonary embolism, cardiac tamponade or pulmonary diseases, were excluded.

The topography of the subthebesian fossa in relation to neighbouring structures within the right atrium.

The majority of anatomical structures within the heart during typical atrial flutters' ablation, right sided accessory pathway ablation or slow pathway ablation are invisible or blurred. Therefore it is very important to know in details interior right atrial structures during such procedures. In the neighborhood of coronary sinus orifice small concavity is visible. This area, called subthebesian fossa, is placed between the os of coronary sinus, the orifice of vena cava inferior and tricuspid annulus. The fossa is on the way of typical atrial flutters' reentrant circuit and is placed next to the isthmus area, which has become a target site for ablative therapy. Regarding the facts mentioned above we decided to examine the topography of this concavity in relation to neighboring structures. Research was conducted on material consisting of 45 human hearts of both sexes, from 19 to 71 years of age. The hearts came from patients whose death was not cardiologic in origin. The topography of the fossa was examined in relation to coronary sinus orifice (diameter A), vena cava inferior orifice (diameter B) and the attachment of the posterior leaflet of the tricuspid valve (diameter C). Besides we measured two perpendicular sizes in the inlet plane of the fossa. There were the longest size (diameter D) and the shortest size of the fossa (diameter E). We also defined deepness of the fossa (diameter F). Diameter A was from to 2 to 7mm (avg. 4.9 +/- 1.4 mm), diameter +/- from 2 to 8mm (avg. 4.0 +/- 1.6 mm) and diameter C from 5 to 9 mm (avg. 7.0 +/- 1.5 mm). The longest size in inlet plane of the concavity (diameter D) was from 12 to 18 mm (avg. 14.1 +/- 1.7 mm) and shortest size (diameter E) was from 7 to 14 mm (avg. 9.0 +/- 1.7 mm). The deepness of the fossa (diameter F) was from 2 to 7 mm (avg. 4.8 +/- 1.2 mm). The subthebesian concavity is inconstant anatomical structure, occurring in all forty five examined hearts (100%). The shape and sizes of the subthebesian fossa were variable in examined group of hearts. Our data suggest that differences in diameters between subthebesian fossa and neighboring structures may have clinical importance during ablation procedure.

The arrangement of muscle fibres in the region of the subthebesian fossa in the aspect of atrial flutter.

The typical atrial flutter is the most common supraventricular tachycardia with reentrant circuit. This tachyarrythmia is based on macroreentry wave going around established anatomic landmarks. The reentry in the inferior right atrial wall passes through narrow isthmus, which is the goal for ablative therapy. The isthmus area is bordered anteriorly by the tricuspid valve and posteriorly by the inferior vena cava, coronary sinus, and eustachian ridge. Near to this area we can find anatomical structure, which can be very important during arising, perpetuation and curing of atrial flutter. The concavity, so-called subthebesian fossa, is on the way of typical atrial flutters' reentrant circuit. Regarding the facts mentioned above we decided to examine the morphology and the arrangement of the muscle fibres in this fossa. Research was conducted on material consisting of 70 human hearts of both sexes from the age of 34 to 72 years. 50 hearts came from patients whose death was not cardiologic in origin. 20 hearts came from humans in whose common atrial flutter was confirmed. We observed the arrangement of muscle fibres in the area of subthebesian fossa. Besides we measured the size and deepness of the subthebesian fossa in both groups of hearts. We found that regular arrangement of muscle fibres within subthebesian fossa was present in 23 healthy human hearts (46%) and 7 cases (35%) of hearts with atrial flutter. The irregular arrangement of muscle fibres was observed in 27 hearts (54%) of control group and 13 hearts (65%) with dysrrhythmia. The thickness of the right atrial wall within the subthebesian fossa was very thin in 8 normal hearts (16%) and in 5 dysrrhythmic hearts (25%). The sizes of examined structure were variable in both groups of hearts, and are presented in the table. It seems that the subthebesian concavity can be the substrate for reentrant circuit during atrial flutter, and there could be such special arrangement of muscle fibres, which allows for microreentrant circuit to arise in this area.

Preliminary study of external interatrial muscle fascicles.

The atria are highly complex multidimensional structures composed of a heterogeneous branching network of subendocardial muscular bundles. The relief of the inner part of the right atrium includes the crista terminalis as well as multiple pectinate muscles that bridge the thinner atrial free walls and appendages. However, a handful of studies have focused attention on the role of the naturally occurring complexities of the atrial subendocardial muscle structures in the mechanisms of cardiac arrhythmias. In accordance with the facts mentioned above, it was decided to examine the morphology and topography of the external interatrial junctions and related structures in order to define the possible anatomical basis of impulse propagation in focal atrial fibrillation. Research was conducted on material consisting of 15 human hearts of both sexes (female--6, male--9) from 18 to 82 years of age. In addition we were concerned, on the basis of the history and electrocardiograph tracings, that none of the patients had shown focal and non-focal type of atrial fibrillation. The classic macroscopic methods of anatomical evaluation were used. The walls of the atria were prepared via a stereoscopic microscope, the pericardium and fatty tissue were eliminated from the surface of the atria, visualising muscle fibres linking both of the atria, and the beginnings and the endpoints of fascicles in the right and left atrium were estimated. The structure, large muscle bundle, was present in all examined hearts. The muscle fascicle was descending from the anterior wall of the right atrium just below the orifice of the superior vena cava. The fascicle, running towards the left atrium, divided into two branches, one of which joined with the superior fascicle from the posterior wall and created one running above the interatrial septum and infiltrating into the wall of the left atrium on its superior surface between the superior pulmonary veins. The other branch of the anterior fascicle was running across the anterior wall of the atria and it penetrated into the left atrium muscle in the region of the inferior pole of the left auricle outlet. On the posterior wall of the atria three types of interatrial fascicles were distinguished: unifascicular, bifascicular and trifascicular. The bifascicular type was the most frequent configuration (9 cases--60.0%), in 5 cases it was trifascicular (33.3%) and finally the unifascicular configuration was observed in just 1 heart (6.7%). On the basis of our study we can conclude that the external interatrial fascicles are the constant structure of the heart, although they may have a variable morphology. Those structures could be responsible for physiological conduction between the atria and may play an important role in patients with atrial fibrillation.