Hydration properties of small hydrophobic molecules by Brillouin light scattering.

We study the relaxation of water molecules next to hydrophobic solutes with different functional groups by Brillouin light scattering. Evidence is given for (i) water activation energy in trimethylamine-N-oxide, proline and t-butyl alcohol diluted solutions which is comparable to that of neat water, almost independent from solute mole fraction and (ii) moderate slowdown of relaxation time of proximal water compared to the bulk, which is consistent with excluded volume models. Assuming that the main contribution to viscosity comes from bulk and hydration water, a rationale is given of the phenomenological Arrhenius' laws for the viscosity of diluted aqueous solutions.

Noncoronary aortic cusp rupture in an adult patient with ventricular septal defect: echocardiographic diagnosis.

Aortic regurgitation is a common complication of ventricular septal defects. The most common mechanism is right or noncoronary cusp prolapse. Other mechanisms are right or noncoronary cusp fibrosis resulting in thickening and restricted motion of the leaflets or infective endocarditis leading to cusp perforation. We describe a case of subacute and severe aortic regurgitation due to noncoronary cusp prolapse resulting in the development of a large aneurysm and rupture of the noncoronary sinus of Valsalva into the right atrium.

Pediatric heart failure.

Heart failure is a clinical syndrome which presents similarities and differences between children and adults; in pediatric age the spectrum of causes of heart failure is wide and congenital heart defects are the most common etiology. Volume and pressure overload on a ''normal myocardium'' is the classical physiological pattern while myocardial contractile dysfunction of different etiology is much less observed in the pediatric population. However there are some peculiarities in clinical presentation of heart failure in infants and small children. The medical therapy cornerstones still remain loop diuretics, angiotensin-converting enzyme inhibitors, beta-blockers and digitalis. There are also some reported experiences with new inotropics drugs in acute heart failure. In pediatric cardiology there are few prospective studies on pharmacology of heart failure and the data are often extrapolated from adult large trials. Non pharmacological treatment with autonomic implantable cardioverter defibrillators and resynchronization therapy as well as the surgically implant of ventricular assist devices are increasingly employed in children. Cardiac transplantation is currently the treatment option with good outcome and long-term survival in pediatric patients with end-stage or refractory heart failure.

Role and effectiveness of cardiovascular magnetic resonance in the diagnosis, preoperative evaluation and follow-up of patients with congenital heart diseases.

The substantial advances in the medical and surgical treatment of congenital heart diseases have dramatically improved patients' life expectancy, as well as increased the number of those needing lifelong monitoring to identify complications and residual defects. Magnetic resonance imaging (MRI) is an ideal imaging modality for the follow-up of these young patients owing to its noninvasiveness, high reproducibility and morphological and functional accuracy. This paper describes the most appropriate MRI techniques and sequences for the study of cardiovascular heart diseases on the basis of an analysis of MRI studies carried out between January 2003 and June 2006 on 274 patients affected by all of the main congenital cardiovascular malformations, as well as a review of the literature. The advantages of MRI with respect to other imaging techniques, the problems encountered and the main clinical applications and indications of MRI, with special reference to the most common disease entities, are then discussed to define the role, the utility and the future perspectives of this imaging technique in the study of congenital heart diseases.

Wide spectrum of presentation and variable outcomes of isolated left ventricular non-compaction.

OBJECTIVES: To investigate diagnostic routes, echocardiographic substrates, outcomes and prognostic factors in patients with isolated ventricular non-compaction (IVNC) identified by echocardiographic laboratories with referral from specialists and primary care physicians. PATIENTS AND DESIGN: Since 1991, all patients with suspected IVNC were flagged and followed up on dedicated databases. Patients were divided into symptom-based and non-symptom-based diagnostic subgroups. RESULTS: 65 eligible patients were followed up for 6-193 months (mean 46 (SD 44). In 53 (82%) patients, IVNC was associated with variable degrees of left ventricular (LV) dilatation and hypokinesia, and in the remaining 12 (18%) LV volumes were normal. Diagnosis was symptom based in 48 (74%) and non-symptom based in 17 (26%) (familial referral in 10). The non-symptom-based subgroup was characterised by younger age, lower prevalence of ECG abnormalities, better systolic function and lower left atrial size, whereas the extent of non-compaction was not different. No major cardiovascular events occurred in the non-symptom-based group, whereas 15 of 48 (31%) symptomatically diagnosed patients experienced cardiovascular death or heart transplantation (p = 0.01, Kaplan-Meier analysis). Independent predictors of cardiovascular death or heart transplantation were New York Heart Association class III-IV, sustained ventricular arrhythmias and left atrial size. CONCLUSIONS: IVNC is associated with a broad spectrum of clinical and pathophysiological findings, and the overall natural history and prognosis may be better than previously thought. Adult patients with incidental or familial discovery of IVNC have an encouraging outlook, whereas those who have symptoms of heart failure, a history of sustained ventricular tachycardia or an enlarged left atrium have an unstable course and more severe prognosis.

Recovery kinetics of oxygen uptake is abnormally prolonged in patients with Mustard/Senning repair for transposition of the great arteries.

The aim of this study was to evaluate the ability to recover from exercise in patients with a Mustard/Senning (M/S) repair for transposition of the great arteries and to identify the major determinants. A total of 40 consecutive patients with a M/S repair at a mean age of 10.0 +/- 9.8 months underwent maximal cardiopulmonary exercise testing at 19.5 +/- 11.3 years of age. Results were compared to those of a cohort of 153 healthy individuals. Decay of oxygen uptake (VO2), CO2 (VCO2), minute ventilation (VE), heart rate (HR) was calculated for the first minute of recovery. M/S patients had reduced peak VO2(22.9 +/- 7.2 vs 34.2 +/- 9.5 ml O2/kg/min, p < 0.0001) and VO2 slope (0.27 +/- 0.10 vs 0.47 +/- 0.2 L O2/min, p < 0.0001), Peak O2 pulse (p < 0.0001) and peak HR (p = 0.001) were reduced. VCO2 and VE slopes were reduced (p < 0.0001 for both), whereas HR slope was similar (p = 0.38). In M/S patients, the only independent determinants of VO2 slope during recovery were pulse O2 slope (p < 0.0001) and VCO2 slope (p < 0.0001). In M/S patients, a limited cardiopulmonary reserve affects not only maximal exercise responses but also the recovery phase. A prolonged recovery of O2 pulse and a prolonged CO2 retention with subsequent prolonged hyperpnea are the main determinants of the delayed recovery.

Surgical repair of naturally palliated anomalous origin of the left coronary artery from the right pulmonary artery.

Anomalous origin of the left coronary artery from the pulmonary arteries is a rare and life-threatening defect, usually needing prompt surgical correction during infancy. We describe the case of a young asymptomatic patient with this defect who underwent surgical reimplantation despite the absence of signs of myocardial ischemia, due to the presence of proximal stenosis of the anomalous coronary artery.

Neonatal aortic arch thrombosis as a result of congenital cytomegalovirus infection.

Thrombotic disease is rare in neonates. The main risk factors at this age are perinatal asphyxia, maternal diabetes, sepsis, polycythemia, dehydration, a low cardiac output, and in primis the catheterization of central lines. Another important risk factor is inherited thrombophilia. Arterial thrombosis is even more rare than venous thrombosis and less related to most of the risk factors listed above; it occurs more frequently in the iliac, femoral, and cerebral arteries but very rarely in the aorta. Most of the described cases of aortic thrombosis are associated with the catheterization of an umbilical artery and involve the descending tract and the renal arteries; very few relate to the ascending tract and the aortic arch. The possible role of virus-induced primary vascular endothelium damage in the etiopathogenesis of neonatal arterial thrombosis has been previously hypothesized. Herpesviruses, particularly human cytomegalovirus (HCMV), can infect endothelial cells and directly damage intact vascular endothelium, altering its thromboresistant surface as a result of procoagulant activity mediated by specific viral surface phospholipids, necessary for the coagulation enzyme complex assembly that leads to thrombin generation. We describe a case of congenital aortic arch thrombosis. The clinical, laboratory, and virologic pictures; the anatomopathologic findings (fully compatible with viral infection); the detection of HCMV in various tissues (including the aorta); and the absence of other causes of aortic thrombosis make it possible to attribute the case to a severe congenital HCMV infection with multiple organ involvement, after the primary infection of the mother. The hemostatic system disorders and hemodynamic disturbances related to viral cardiac damage explain the clinical features of the case and indicate that congenital HCMV infection should be included among the causes of neonatal aortic thrombosis.

Midterm follow-up of the Amplatzer device in left ventricle-to-aorta conduits.

The midterm follow-up of 2 patients with left ventricle-to-aorta conduit who underwent percutaneous closure with the Amplatzer device is described. Complete occlusion was achieved immediately in 1 patient. In the other patient, a trivial residual shunt was still present after 12 months, but disappeared after 18 months. Occlusion of dysfunctional left ventricle-to-aorta conduits by the Amplatzer device is feasible, provided that enough time is allowed for complete occlusion.

Neurocardiogenic syncope in selected pediatric patients--natural history during long-term follow-up and effect of prophylactic pharmacological therapy.

OBJECTIVE: The natural history of pediatric patients with severely symptomatic neurocardiogenic syncope is poorly defined respect to the likelihood of remission or symptomatic recurrence along time. We undertook this study to investigate the likelihood of clinical relapse, and to assess the effect of prophylactic pharmacological treatment in the most symptomatic patients. METHODS: Twenty-nine patients with neurocardiogenic syncope were studied at our Institution: 14 (12 +/- 3.6 years) highly symptomatic received prophylactic therapy with beta-blockers guided by head up tilt (HUT), whereas 15 (12.2 +/- 2.7 years) moderately symptomatic received only education to avoid triggering of the vasovagal reflex and to abort forthcoming syncope. Patients were then followed respectively for 33.7 +/- 9.0 and 33.3 +/- 8.7 months (p = NS). RESULTS: The average duration of symptoms before HUT was 9.0 +/- 4.3 months (range 3-17) for treated patients, and 6.2 +/- 2.5 months (range 2-11) for those untreated (p < 0.05). Treated patients had also a greater number of symptomatic events: 6 +/- 2 vs. 2 +/- 1 (p < 0.001). During follow up, 9/15 untreated and 6/14 treated patients had at least 1 recurrence, with an odds ratio of 2 (95% CI 0.72-5.49). Clinical events were greatly reduced in both groups at follow up, but treated patients had a significantly greater reduction either of syncopal (p < 0.001) or near syncopal events (p < 0.02). Time to the first recurrence, syncope or near syncope, was shorter for untreated vs treated patients: 5 +/- 2 vs. 25 +/- 12 months (p < 0.001). Looking at the time course of all clinical recurrences, 23/26 occurred in untreated patients, whereas 7/10 occurred in treated patients within 24 months. An attempt to therapy discontinuation was made after 30 months in 4 patients, and resulted in half of them being asymptomatic, and half with a single minor recurrence. CONCLUSIONS: Spontaneous reduction of symptoms occurs along time in pediatric patients with neurocardiogenic syncope, so that recurrences are very unlikely after 24 months from first diagnosis. Tiered prophylactic therapy may be guided by HUT in selected highly symptomatic patients; beta-blockers appear a very effective intervention. Larger, prospective controlled studies are required to investigate the role of any intervention in moderately symptomatic patients.

Surgical treatment of secundum atrial septal defect in patients older than 50 years.

BACKGROUND: The aim of this study was to verify if surgery is beneficial for patients older than 50 years. METHODS: Sixty-five patients older than 50 years were operated for a secundum atrial septal defect between November 1974 and November 1998. Preoperative data were obtained from hospital records; postoperative data from written questionnaires or direct telephone interviews. A comparison of pre and postoperative data was possible in 53 patients. RESULTS: The operative mortality was 0%. One patient died of a thromboembolic complication 32 days after surgery. The mean follow-up was 9 +/- 6 years. After surgery, clinical improvement occurred in 22 patients (41.5%) with the majority of them (69.8%) being asymptomatic or only mildly symptomatic. The occurrence of atrial fibrillation/flutter did not decrease after surgery (39.6 vs 26.4%). A thromboembolic event occurred in 2 patients before surgery and in 2 patients postoperatively; all of them had supraventricular arrhythmias and were not taking anticoagulants. CONCLUSIONS: Surgical closure of atrial septal defects in patients older than 50 years is feasible. The mortality is low. In this age group, surgery has a beneficial effect on the clinical status of the patients but not on the occurrence of supraventricular arrhythmias that can affect morbidity and mortality in patients who are not treated with anticoagulants.

Turner's syndrome: cardiologic profile according to the different chromosomal patterns and long-term clinical follow-Up of 136 nonpreselected patients.

The preferential association between Turner's syndrome and congenital heart defects (CHD) have been well known since the first description by Morgagni. There are few studies about the different cardiologic problems stemming from different chromosomal patterns of X monosomies. We reviewed a large series of 136 patients with Turner syndrome without cardiologic preselection, 29 of whom had some kind of CHD (21.5%). Partial anomalous pulmonary venous drainage (PAPVD; 2.9%), aortic valve disease (stenosis and/or incompetence) (AoVD; 5. 1%), aortic coarctation (AoCo; 4.4%), and bicuspid aortic valve (BicAo; 14.7%) are much more frequent in Turner's syndrome than in the normal population, with the difference being statistically highly significant. In our cases, only the 45, X subjects showed severe CHD and multiple lesions, whereas the X-ring pattern was associated with an elevated prevalence of BicAo. Patients with X-deletion showed no signs of congenital heart malformations. Eleven patients, all with 45, X pattern, and significant CHD, underwent cardiac surgery at a mean age of 7.7 +/- 5.3 years (range 7 days-18 years) without complications. At follow-up of 3-18 years (8.6 +/- 5. 2), we were unable to observe any type of evolution of the remaining untreated cardiovascular anomalies.

Noonan syndrome and aortic coarctation.

Congenital heart defect (CHD) is present in half of the propositi with Noonan syndrome (NS). Aortic coarctation (AC) is rarely seen in NS, since only three male patients with NS and AC have been previously reported. On the other hand, AC is common in the Ull-rich-Turner syndrome, an aneuploidy disorder and not a mendelian syndrome. In order to evaluate if AC is truly rare in patients with NS, we reviewed our series of 184 propositi with NS and CHD. AC was diagnosed in 16 (8.7%) patients. There were 11 males and 5 females. All had normal chromosomes. Clinical characteristics of the patients are described. Familial occurrence was detected in one girl with NS and AC whose mother and sibs also had NS, but different form of CHDs. Thus, AC is more frequent in NS than previously reported.