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Background: The normal human heart behaves as a single functional unit during preload reduction; adaptations of the left ventricle to head-up tilting is mediated through ventricular interdependence and biventricular-lung interaction., Hypothesis: We hypothesized that reduction of venous return in dilated cardiomyopathy is likely to have a great effect on ventricular chamber geometry and filling. The aim of this study was to evaluate the effects of gradual head-up tilting in normal subjects and in patients with dilated cardiomyopathy, addressing special attention to right (RV) and left ventricular (LV) dimensions, geometry, and filling, and to biventricular-lung interaction., Methods: Twenty normal subjects and 23 patients with moderate heart failure due to dilated cardiomyopathy were studied with two-dimensional and Doppler echocardiography in supine position and after 20 degrees, 40 degrees, and 60 degrees tilting. Right ventricular and LV dimensions, LV geometry, and tricuspid, mitral, and pulmonary venous flow patterns were recorded at each step of the study. Geometric changes of the LV were evaluated by measurements of volumes and diameters in the apical four-chamber view (which identifies the interventricular septum and lateral wall) and apical two-chamber view (which identifies the inferior and anterior wall of the LV)., Results: In the two groups, tilting was associated with reduction of RV area and LV diameter and volumes; percent variations in LV diameter and volumes recorded in four-chamber view were lower at each step of tilting than with those derived from the two-chamber view in controls and in patients. In normal subjects, mitral and tricuspid peak early flow velocities were decreased at any tilting level; peak late velocities were unchanged; peak velocity of systolic forward flow of the pulmonary vein was reduced, diastolic forward flow was unchanged, and the difference in duration between reverse pulmonary flow and forward mitral A wave was reduced. Doppler findings were qualitatively similar in patients, but tilting induced a more marked redistribution of LV filling to late diastole because of a significant increase in atrial contribution., Conclusions: Preload reduction by tilting induces profound effects on left and right dimensions, geometry, and filling in normal and dilated heart; reduction or RV dimensions are associated with changes in LV ventricular geometry (minimal reduction in septal-lateral diameter, marked reduction in anterior-posterior diameter), redistribution of right and left diastolic filling to late diastole, and redistribution of pulmonary venous flow to early diastole. These mechanisms are probably due to a favorable interaction between heart and lungs, which increases compliance within the pericardial space and facilitates redistribution of flow from the lungs. Even a minimal amount of preload reduction causes more marked effects in LV filling patterns in dilated cardiomyopathy than in normal hearts, confirming that ventricular interaction and pericardial constraint are increased when heart volume enlarges.

Periodic breathing may be observed in patients with severe congestive heart failure during exercise. We describe a patient with such a breathing pattern. We noted that nadir of oxygen consumption cycles slightly preceded the nadir of ventilation cycles, suggesting that this breathing pattern is due to cardiac output periodic changes, possibly through an interplay among the two ventricles and the pulmonary blood reservoir.

The sinus node artery (SNA) arises from the right coronary artery in near 60% of the cases and from the left circumflex artery in the remaining ones. We described the case of a patient in whom the SNA took off from the proximal part of the left main trunk. A 59 year-old male underwent coronary arteriography because of unstable angina. Soon after the incannulation of the left coronary ostium with a 7F catheter critical bradycardia ensued without ECG changes of ischemia. The arrhythmia spontaneously reverted by removing the catheter. Further contrast injections were carried out with a smaller diagnostic catheter (5F); the left main trunk was normal with the SNA arising from the very proximal part of it. It is likely that the heart rate slowing was elicited by a temporary occlusion (and related ischemia) of the anomalous SNA by the diagnostic catheter. This anomaly may therefore provoked heart arrhythmias during diagnostic or interventional procedures.

Renin-angiotensin system promotes sodium and chloride retention, participates in the defense response to hypovolemia and, in congestive heart failure, contributes to edema formation and progression of the disease. We investigated whether ACE-inhibitors interfere with the action of the renin-angiotensin system on the nephron, and therefore with water and urinary electrolytes excretion. The interaction among renin-angiotensin system, diuretic treatment and urinary electrolytes was evaluated both during chronic treatment and in response to acute renin-angiotensin system activation as that observed after extracorporeal ultrafiltration-induced transient hypovolemia. Plasma renin activity and aldosterone, body fluid balance and urinary sodium, chloride and potassium concentrations were evaluated in 30 patients with congestive heart failure in NYHA II-III functional class, grouped according to whether long-term therapy did not include (Group I, n = 15) or included (Group II, n = 18) ACE-inhibitors. All parameters were evaluated at baseline and after a single session of extracorporeal ultrafiltration. At baseline, urinary output and urinary sodium and chloride concentrations were similar in the two groups, while urinary potassium concentration was lower in patients assuming ACE-inhibitors (Group II). Plasma renin activity was higher and aldosterone was lower in Group II than in Group I. After removal of similar amounts of plasma water by extracorporeal ultrafiltration, body weight decreased in both groups but the decrease was maintained in the following days only in Group II patients. A transient reduction (48 hours) of both plasma volume and urinary output was observed after ultrafiltration in both groups. Despite plasma renin activity and aldosterone increase, urinary electrolytes response to ultrafiltration was different in the two groups: sodium and chloride were reduced, and potassium did not change in Group 1 while, in Group II, sodium and chloride did not change and potassium excretion was significantly increased. In conclusion, chronic treatment with ACE-inhibitors does not enhance the excretion of sodium in congestive heart failure but just mitigates potassium loss. The role of these drugs becomes particularly relevant during acute renin-angiotensin system activation due to hypovolemia; in this setting ACE-inhibitors counteract sodium and chloride retention resulting in a potential hazard due to interference with the defence mechanisms toward hypovolemia, and an amplification of extracorporeal ultrafiltration efficacy by preventing edema recovery after its mechanical removal.

Carcinoid tumors are among the most frequently neuroendocrine neoplasms of the gastrointestinal tract. They occur more commonly as benign diseases but malignant ones can also be found. The peak age incidence varies with the location of the tumor, with appendiceal tumors being diagnosed at an overage of 36 years, whereas non appendiceal tumors are found typically in the fifth sixth decades of life. There is no sex predilection of the tumors. Most carcinoid tumors are found within the appendix (40-50%) or small intestine (25%). Less common sites include the rectum (15%), main bronchus (10%), duodenum (3-8%) and stomach (2%). Most carcinoid tumors are found incidentally at operation and cause no symptoms. If symptoms do occur, they can be either non specific include intermittent crampy abdominal pain, vomiting and distension caused by intestinal obstruction. The prognosis depends on the site of the tumor and its size. Most carcinoid tumors (75%) are less than 1 cm in size and only 5% are greater than 2 cm. The incidence of metastatic disease is related directly to the size of the tumor at all locations. Carcinoid tumor with size less than 1 cm give linfonodal metastasis only in 3-5%; the other with size over 2 cm give metastasis in the 70-75% of the cases. The 5-years survival for all carcinoid tumors are approximately 85%. Five years rate is higher (> 80%) in carcinoid tumors of appendix and rectum than in gastroduodenal, ileal and colonic neoplasm (< 60%). In this paper the authors report a case of malignant carcinoid of the duodenum.