Microscopic fractional anisotropy outperforms multiple sclerosis lesion assessment and clinical outcome associations over standard fractional anisotropy tensor.

We aimed to compare the ability of diffusion tensor imaging and multi-compartment spherical mean technique to detect focal tissue damage and in distinguishing between different connectivity patterns associated with varying clinical outcomes in multiple sclerosis (MS). Seventy-six people diagnosed with MS were scanned using a SIEMENS Prisma Fit 3T magnetic resonance imaging (MRI), employing both conventional (T1w and fluid-attenuated inversion recovery) and advanced diffusion MRI sequences from which fractional anisotropy (FA) and microscopic FA (µFA) maps were generated. Using automated fiber quantification (AFQ), we assessed diffusion profiles across multiple white matter (WM) pathways to measure the sensitivity of anisotropy diffusion metrics in detecting localized tissue damage. In parallel, we analyzed structural brain connectivity in a specific patient cohort to fully grasp its relationships with cognitive and physical clinical outcomes. This evaluation comprehensively considered different patient categories, including cognitively preserved (CP), mild cognitive deficits (MCD), and cognitively impaired (CI) for cognitive assessment, as well as groups distinguished by physical impact: those with mild disability (Expanded Disability Status Scale [EDSS] <=3) and those with moderate-severe disability (EDSS >3). In our initial objective, we employed Ridge regression to forecast the presence of focal MS lesions, comparing the performance of µFA and FA. µFA exhibited a stronger association with tissue damage and a higher predictive precision for focal MS lesions across the tracts, achieving an R-squared value of .57, significantly outperforming the R-squared value of .24 for FA (p-value <.001). In structural connectivity, µFA exhibited more pronounced differences than FA in response to alteration in both cognitive and physical clinical scores in terms of effect size and number of connections. Regarding cognitive groups, FA differences between CP and MCD groups were limited to 0.5% of connections, mainly around the thalamus, while µFA revealed changes in 2.5% of connections. In the CP and CI group comparison, which have noticeable cognitive differences, the disparity was 5.6% for FA values and 32.5% for µFA. Similarly, µFA outperformed FA in detecting WM changes between the MCD and CI groups, with 5% versus 0.3% of connections, respectively. When analyzing structural connectivity between physical disability groups, µFA still demonstrated superior performance over FA, disclosing a 2.1% difference in connectivity between regions closely associated with physical disability in MS. In contrast, FA spotted a few regions, comprising only 0.6% of total connections. In summary, µFA emerged as a more effective tool than FA in predicting MS lesions and identifying structural changes across patients with different degrees of cognitive and global disability, offering deeper insights into the complexities of MS-related impairments.

Diffusion tensor imaging metrics associated with future disability in multiple sclerosis.

The relationship between brain diffusion microstructural changes and disability in multiple sclerosis (MS) remains poorly understood. We aimed to explore the predictive value of microstructural properties in white (WM) and grey matter (GM), and identify areas associated with mid-term disability in MS patients. We studied 185 patients (71% female; 86% RRMS) with the Expanded Disability Status Scale (EDSS), timed 25-foot walk (T25FW), nine-hole peg test (9HPT), and Symbol Digit Modalities Test (SDMT) at two time-points. We used Lasso regression to analyse the predictive value of baseline WM fractional anisotropy and GM mean diffusivity, and to identify areas related to each outcome at 4.1 years follow-up. Motor performance was associated with WM (T25FW: RMSE = 0.524, R2 = 0.304; 9HPT dominant hand: RMSE = 0.662, R2 = 0.062; 9HPT non-dominant hand: RMSE = 0.649, R2 = 0.139), and SDMT with GM diffusion metrics (RMSE = 0.772, R2 = 0.186). Cingulum, longitudinal fasciculus, optic radiation, forceps minor and frontal aslant were the WM tracts most closely linked to motor dysfunction, and temporal and frontal cortex were relevant for cognition. Regional specificity related to clinical outcomes provide valuable information that can be used to develop more accurate predictive models that could improve therapeutic strategies.

Transtracheal aspiration and fine needle aspiration biopsy for the diagnosis of pulmonary infection in heart transplant patients.

A total of 129 transtracheal aspirations or fine needle aspirations, or both, were performed in 65 heart and heart-lung transplant patients to identify the causative pathogen in suspected pulmonary infection. Transtracheal aspiration was performed in 82 instances, fine needle aspiration in 47, and both procedures in 23. Both transtracheal and fine needle aspiration were highly specific, 96% and 100%, respectively. Sensitivity for transtracheal aspiration was lower than for fine needle aspiration, 70% and 89%, respectively. The lower sensitivity of transtracheal aspiration is attributed to its performance in all patients with suspected infection regardless of chest radiographic findings. Fine needle aspiration was performed when identifiable lesions could be used as a "target." Overall accuracy of transtracheal aspiration was 78% compared to 91% for fine needle aspiration both alone and combined with transtracheal aspiration. More invasive procedures such as bronchoalveolar lavage and open lung biopsy were required in only three patients (2%). Transtracheal aspiration resulted in one minor complication (1%). The commonest complication of fine needle aspiration was pneumothorax (21%). There were no deaths associated with either procedure. We conclude that in heart and heart-lung transplant patients with suspected pulmonary infection, transtracheal aspiration and fine needle aspiration are safe and accurate methods to identify the causative organism. More invasive techniques may be required in a small minority of patients.

Surgical pathology of the aortic valve: gross and histological findings in 1120 excised valves.

From January 1981 through December 1991, 1120 consecutive aortic valves were surgically explanted and their gross anatomy and histology studied at our university. Rheumatic disease (65%), dystrophic calcific valvular disease (23%), noninflammatory disease of the aortic root and/or floppy aortic valve (6.3%), and endocarditis (5.4%) were the causes of valve dysfunction. Among the total population the male sex predominated. The male to female ratio was 2.4 in the group with dystrophic calcific valvular disease and 1.6 in the group with bacterial endocarditis. The mean age was 37 ± 7.5 years in the group with non-inflammatory disease of the aortic root and/or aortic cusps. In the group with dystrophic calcific valvular disease, the mean age was 62 ± 6.3 years. Among the 1120 patients, 717 (64.03%) underwent surgery for aortic stenotic-incompetence, 250 (22.25%) for isolated aortic stenosis, and 153 (13.72%) for isolated aortic incompetence. In 449 cases (40.13%) a mitral pathology was associated. Chronic rheumatic aortic disease usually caused stenotic insufficiency (92.8%). Dystrophic calcific aortic disease caused pure stenosis in 84.8% of the cases. Among these, 46 patients (18.4%) had a congenitally bicuspidal aortic valve. Pure aortic incompetence was caused by noninflammatory aortic root and/or cusp disease in 44% of patients, infective endocarditis in 40%, and rheumatic disease in 16%. Patients with noninflammatory aortic root and/or cusp disease were divided into three groups: 29 patients with aortic root dilatation and normal cusps, 25 patients with aortic root dilatation and mixomatous infiltration of aortic cusps (floppy aortic valve), and 15 patients with floppy aortic valve and normal aortic root. Aortic incompetence was caused by cusp retraction caused by chronic rheumatic disease, cusp perforation or tears caused by infective endocarditis, and cusp prolapse for floppy aortic valve. Cusp diastasis has been the cause of aortic incompetence in patients with dilated aortic root. In patient with floppy aortic valve caused by the fibrous lamina disarray, the cusps prolapsed toward the left ventricle, causing valve regurgitation.

Role of the heart surgeon in the emergency treatment of diuretic resistant edema in grades III-IV heart failure.

Acute or chronic valvular diseases, acute myocardial infarction and its complications, dilated cardiomyopathies, all may became the cause of heart failure leading to different degrees of cardiogenic edema. Today cardiac failure is treated from its the early stage by medical and/or surgical therapy. Thereafter, in a small population of patients, heart failure may became unresponsive to any kind of standard medical treatment. Conventional surgical procedures are often inadequate and carry a high risk of perioperative mortality. This study analyzes the outcome of 139 patients with end-stage cardiomyopathy who underwent heart transplantation between January 1988 and October 1996. We found that patients transplanted while on severe decompensation are at a higher perioperative mortality due to irreversible multi-organ failure. The study also suggests that the implantation of a left ventricle assist device as a bridge to transplantation is a promising maneuver for the most severe patients.

Non-inflammatory aortic root disease and floppy aortic valve as cause of isolated regurgitation: a clinico-morphologic study.

A clinico-morphologic study was performed on 1120 patients who underwent aortic valve replacement at the Department of Medical and Surgical Cardiology, 2nd University Medical School of Naples, Naples, Italy, from January 1981 through December 1991. In 69 cases the aortic valve was incompetent due to a non-inflammatory aortic root disease such as myxomatous infiltration of the cusps and or aortic root dilatation. Among these patients males were prevalent (male/female ratio = 2.2). The mean age was 37 +/- 7.5 years. A floppy mitral valve was diagnosed in 16 cases while in one a left atrial myxoma was found. The patients were divided into 3 groups: Group 1-29 patients with aortic root dilatation and normal cusps; Group 2-25 patients with aortic root dilatation and myxomatous infiltration of aortic cusps (floppy aortic valve); and Group 3-15 patients with floppy aortic valve and undilated aortic root. At the gross examination the cusps of the patients in Groups 2 and 3 were redundant, thin, soft and gelatinous. The histology showed myxomatous infiltration with disruption of the fibrous layer. In patients with aortic root dilatation the histology of the aortic root fragments showed a cystic medial necrosis. Deep correlation was found between the root dilatation and the grade of aortic wall cystic medial necrosis. Cusp's diastasis was the cause of aortic regurgitation in patients with aortic root dilatation, while cusp prolapse caused aortic incompetence in presence of the floppy aortic valve and undilated aortic root.(ABSTRACT TRUNCATED AT 250 WORDS)

Intermediate and late follow-up of the use of apico-aortic conduits in the surgical treatment of hypertrophic cardiomyopathy.

Between December 1977 and July 1983, four apico-aortic prosthetic valved conduits were implanted in four patients affected by severe hypertrophic cardiomyopathy. The disease was isolated in two cases, associated with critical stenosis of the right coronary artery in one case and with a subaortic tunnel plus aortic valve regurgitation in the final case. Three patients were male and one female; the ages ranged from 6 to 49 years. All patients survived surgery and were followed-up. At present, all are living and have no postoperative symptoms. The left ventricular-aortic gradient was relieved in all cases. Echocardiographic studies during the follow-up showed an enlargement of the left ventricular cavity with a satisfactory cardiac contraction. Three years following surgery the female patient gave birth to a normal male baby. Her pregnancy was normal and without complications. Seven years after surgery the first patient was successfully reoperated because of conduit thrombosis caused by degeneration of the biological porcine valve. In the follow-up, which ranges from 18 months to 7 years (mean 4.5 years) all patients are in Functional Class I. All preoperative symptoms have been relieved for all patients and there has been no incidence of late or sudden death.

Surgical pathology of the mitral valve: gross and histological study of 1288 surgically excised valves.

A consecutive series of 1288 mitral valves surgically excised from 1981 through 1989 were studied macroscopically and histologically. The explanted valves were affected by: chronic rheumatic disease (1179, 91.5%), floppy mitral valve (84, 6.5%), bacterial endocarditis (19, 1.5%), and post-ischemic mitral incompetence (6, 0.5%). Among 1179 post-rheumatic cases, mixed mitral stenosis and incompetence was the most frequent malfunction (747, 58%). Isolated mitral incompetence was diagnosed in 72 (6.11%) cases only, and isolated stenosis in 360 cases. In 52 valves, excised because of chronic rheumatic disease, the histology showed unexpected signs of acute rheumatism of the leaflets and the papillary muscles. In these patients clinical symptoms and blood tests were negative for rheumatic disease. Mitral incompetence, possibly due to papillary muscle dysfunction, was the prevalent lesion (61.5%). A total of 181 patients (14.05%) with pure mitral incompetence underwent surgery. In 84 patients (46.4%), the floppy mitral valve was the most frequent cause of valve dysfunction, 72 (39.8%) had rheumatic disease, 19 (10.5%) infective endocarditis, and 6 (3.4%) ischemic heart disease. In the group with floppy mitral valve, males were more prevalent than females (51:33). The mean age of the 4 patients with Marfan's syndrome and non-Marfan patients was noticeably different (17 vs 49 yr). Moreover leaflet deformation, tendinous cord elongation and annulus dilatation were the most common causes of valve incompetence. Floppy mitral valve and infective endocarditis were the cause of cordal rupture in 43.5% of the cases. This was a severe complication which always required emergency surgery.

Early experience with the Jyros bileaflet valve in the mitral position: high incidence of valve thrombosis.

The Jyros valve is a new bileaflet valve with the unusual feature that the hinge is expected to rotate continuously inside the housing. Nine isolated Jyros mitral prostheses were implanted from July to October 1993. All patients survived the surgical procedure and during the follow up underwent transthoracic (TTE) and transesophageal echocardiograms (TEE) for the evaluation of hinge rotation. Neither TTE nor TEE were able to show hinge rotation in any patient at any time. Five patients had prosthetic thrombosis. In the successfully treated with thrombolysis. In the remaining patient thrombolysis was contraindicated. Eight patients are alive; one died of gastro-intestinal bleeding a few months after discharge. The absence of hinge rotation may be the triggering mechanism of valve thrombosis although no explanted prostheses were available for examination. Further studies are necessary to understand the mechanism of valve thrombosis with the Jyros bileaflet prosthesis.

Long term results of surgery for prosthetic valve endocarditis.

Operative mortality, recurrence and late survival were analyzed in 64 patients operated for prosthetic valve endocarditis (PVE) between 1980-1992: age, sex, drug addiction, early vs. late PVE, micro-organism, sepsis at the time of surgery, indication for surgery, prosthesis type and site were assessed as potential risk factors. PVE developed after replacement for native valve endocarditis in 23 cases (Group A) and after replacement for other valvular disease in 41 patients (Group B). The overall operative mortality was 28.1% (18/64); 16 operative survivors underwent a second reoperation with eight operative deaths (50%), four of them a third procedure with two operative deaths (50%), and one patient had a successful fourth intervention. Female sex (p = 0.015) and sepsis at the time of surgery (p = 0.013), were found statistically significant independent predictors of operative mortality. Age (p:0.002), mechanical valves (p:0.05) and mitral position (p:0.03) were significant predictors of PVE recurrence. None of the risk factors considered were significant for late survival. Twelve-year actuarial survival for all patients was 52.11 +/- 10%; it was 33.3 +/- 13% for Group A and 73.4 +/- 14% for Group B (p:0.04). Patients with mechanical valves and bioprostheses had an actuarial survival of 39.5 +/- 15% and 48.5 +/- 14% respectively with no significant difference. PVE is still a challenging complication of heart valve replacement; patients with PVE after native valve endocarditis have a very poor outcome. Prompt prosthetic replacement is recommended whenever the antibiotic treatment is unsuccessful and/or the hemodynamic status deteriorates.

Prosthetic creation of a double outlet left ventricle: clinical experience of five cases.

Five clinical cases were treated with the implantation of an apical-aortic conduit. Two adult patients were affected by obstructive myocardiopathy associated to subaortic membrane in one case, and three children by different forms of aortic stenosis (subaortic tunnel in one case; subaortic tunnel associated to severe coartation of the thoracic aorta in one case; aortic annulus hypoplasia in one case). A double outlet left ventricle has been created in all cases by implanting a composite prosthesis between the apex by implanting a composite prosthesis between the apex of the left ventricle and the aorta. The extracardiac conduit consisted of an apical curved connector and a valved dacron tubular prosthesis. The site of implantation was the supraceliac abdominal aorta in three cases and the ascending aorta in two cases. All patients survived the operation and one late mortality was observed for cerebral bleeding. The surviving patients have been restudied with satisfactory data.

Bioelectrical impedance analysis before and after Novacor implantation.

In this study Bioelectrical Impedance Analysis was performed in 5 patients with end stage heart failure in whom a left ventricular assist device (Novacor) was successfully implanted. Whole body measurements of bioelectrical indices resistance and reactance were taken before surgery and 3, 7, 12, and 15 days after it. After surgery there was a significant decrease in reactance, indicating a shift of body fluids from intra- to extra-cellular space.

Impact of graft size and resuspension level of the commissures on aortic insufficiency after reimplantation of the aortic valve.

BACKGROUND: In addition to the size of the graft, the resuspension of the commissures has been described as important for valve function in valve-sparing aortic root replacement procedures. This study describes the influence of a stepwise reduction of the fixation level of the commissures within the graft as well as a stepwise reduction of graft size on valve insufficiency. METHOD: Porcine aortic valves were reimplanted into a tubular graft and the height of the commissures was reduced in a stepwise manner. In a second series of experiments, the diameter of the grafts was reduced by 30 % and 50 %. RESULTS: A reduction of the commissure heights by 10 % and 20 % caused a significant increase in reflux water. Using the criteria of homograft preparation, a 10 %, but not a 20 %, reduction was tolerated. The coaptation level of the valve became increasingly lower, indicating a higher risk for late valve incompetence. A reduction of the prosthesis diameter by 30 % and 50 % did not result in insufficiency of the valve but it lowered the coaptation level. CONCLUSION: Resuspension of the commissures within the graft has a more important impact on early failure rates than the choice of graft size.

[Infective endocarditis today; heart surgery in its treatment: how and when]. / L'endocardite infettiva oggi; la cardiochirurgia nella terapia: come e quando.

The authors report the experience of 161 surgical cases operated between 1980 and 1992 because of valve endocarditis. Two hundred and two surgical procedures were performed. Patients were divided into two groups: Group I (EN) considered 117 patients with endocarditis on the native valve; Group II (EP) included 64 patients with prosthetic endocarditis. In 23 patients the prosthesis was implanted for previous endocarditis on the native valve (EP1); in 41 patients the prosthesis was implanted for other valve diseases (EP2). Each group was described according to sex, age, site of endocarditis, previous cardiac diseases, socio-economical level, hemodynamic and infective conditions at surgery, etiology of endocarditis, surgical indication, pathology report, surgical procedure and results. The results were evaluated considering surgical mortality, late mortality and recurrence of endocarditis. The main risk factors were correlated to overall survival and recurrency. Hospital mortality was 7.6% in EN, 13% in EP1, 36.5% in EP2; endocarditis recurrency was 20.3% in EN, 65% in EP1, 19.2% in EP2. Sixteen patients with prosthetic endocarditis were submitted to a second reoperation with 50% mortality; 4 patients to a third reoperation with 50% mortality; 1 patient to a fourth reoperation with no mortality. Actuarial overall survival was 40.3% at 12 years in Group EN, 33.3% at 12 years in Group EP1, 73.4% at 12 years in Group EP2. Finally the Authors report the experience of 12 stentless grafts (autologous, homologous and eterologous) implanted between March 1991 and July 1994 in patients with valve or prosthetic endocarditis with no recurrency at 42 months of follow-up.

Ascending aorta to femoral arteries by-pass: a safe surgical technique of lower limb revascularization in high risk patients undergoing coronary artery by-pass.

The coexistence of a coronary artery obstructive disease (CAOD) with aorto-iliac obstructive disease (AIOD) often represents a surgical problem. Because of left main coronary disease (LMCOD) the contemporary correction of AIOD should be performed with a simple non traumatic procedure. The case of a high risk patient in whom aortoiliac obstructive disease has been corrected with the implantation of a bifurcated vascular prosthesis from the ascending aorta to the bilateral common femoral arteries, and with a double aorto-coronary by-pass, is reported.

[Endomyocardial biopsy in heart transplantation: the experience of the Naples Center]. / La biopsia endomiocardica nel trapianto cardiaco: esperienza del centro napoletano.

From January 1988 through August 1992, 38 cardiac transplants were performed. 385 endomyocardial biopsies (EMBs) from 32 cardiac allograft recipients were investigated. In 21 (5.45%) EMBs the specimens were inadequate for the diagnosis. In the remaining 364 EMBs the grades of acute rejection were: minimal in 213 (58.51%) EMBs, mild in 132 (36.26%), mild/moderate in 12 (3.3%) and moderate in 7 (1.93%). The most reliable histologic feature of acute rejection was the myocyte necrosis or damage in presence of pironinophilic mononuclear cell infiltrate, so our therapeutic protocol requires myocyte damage to perform an additional treatment, which was performed in 7 cases (1.93%). An intermediate grade mild/moderate, was introduced to classify the EMBs in which the myocyte necrosis was scant or not clear. In these patients another EMB was performed after 3 or 5 days. One patient died of chronic rejection 17 months after the transplant. Changes not related to acute rejection were: ischemic early or late necrosis; changes related to previous biopsy site; subendocardial infiltrate of mononuclear cells (Quilty's alteration); focal, diffuse or perimyocytic fibrosis and artefacts as contraction bands; nuclear or cytoplasmic vacuolar alterations. Some of these changes occasionally made the diagnosis hard or the specimens inadequate for the diagnosis. In spite of these diagnostic difficulties, the EMB is a safe and reliable invasive investigation which plays an important role in the management of rejection in cardiac allograft recipients.

[Surgical pathology of the aortic valve: a morphologic study on 912 surgically excised valves]. / "Surgical pathology" della valvola aortica: studio morfologico su 912 espianti chirurgici.

A consecutive series of 912 surgically excised aortic valves was evaluated by means of macroscopic and histologic study. Pure aortic stenosis was diagnosed in 203 patients (p.) (22.25%), pure incompetence in 125 (13.72%) and combined dysfunction in 584 (64.03%). The diseases affecting the valves were: a) chronic rheumatic disease (593 p., 65%); b) dystrophic calcifications (214 p., 23%); c) noninflammatory aortic root disease (NIARD) and/or myxomatous infiltration of aortic cusps, floppy aortic valve (FAV) (55 p., 6%) d) infective endocarditis (50 p., 5.5%). Males outnumbered females with a ratio ranging from 2.4 (dystrophic calcific disease) to 1.6 (infective endocarditis). The mean age ranged from 37 +/- 7.5 (NIARD) to 61.2 +/- 6.3 (dystrophic calcific disease). Chronic rheumatic disease was the most frequent cause of stenoincompetence (542 p., 91.4%) while isolated stenosis was prevalently due to dystrophic calcification (172 p., 80.4%). The diseases causing isolated aortic incompetence were (in order of frequency): a) NIARD and/or FAV (55 p., 44%); b) infective endocarditis (50 p., 40%); and c) rheumatic disease (30 p., 16%). The 55 patients with NIARD and or FAV were divided into 3 groups: a) 23 p. with aortic root dilatation and normal cusps; b) 20 p. with aortic root dilatation and FAV; c) 12 p. with FAV but undilated aortic root. Aortic regurgitation was caused by cusp derangement in rheumatic disease (shortening, retraction) and infective endocarditis (perforations, erosions). Cusps diastasis and prolapse were the cause of regurgitation in aortic root dilatation.(ABSTRACT TRUNCATED AT 250 WORDS)