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Guido Sani

Publications and source records attributed to Guido Sani.

13 recordsLinked to original sources
PubMed2006

An evaluation of the Ross operation in adults.

BACKGROUND AND AIM OF THE STUDY: Pulmonary autograft replacement of the aortic valve (the Ross operation) is the operation of choice in infants and children. Although this procedure can offer theoretical advantages at any age, its use in adults remains controversial. METHODS: A total of 264 consecutive patients (203 males, 61 females; mean age 35.0 +/- 11.5 years; range: 18-66 years) was studied. These patients underwent the Ross operation at two institutions and were followed up for a total of 1,634 patient-years. The etiology was mainly congenital (52%), degenerative (22%), and rheumatic (8%). Among patients, 21% underwent prior aortic valve replacement. RESULTS: Thirty-day mortality was 2.3% (n = 6), and four more patients died during follow up (mean follow up 6.2 years; range 0-15.4 years). Cumulative survival at five years was 96.8%, and at 10 years was 95.4%. Eleven patients underwent reoperation on the aortic valve; this was due to progressive dilatation and aortic regurgitation in 10 cases, and to dissection of the arterial wall of the autograft in one case. Overall freedom from pulmonary homograft reoperation was 94.9% at 10 years, and for autograft reoperation was 92.9%. Estimated freedom from autograft reoperation at Harefield was 98.6% at five and 10 years, and at Rotterdam 96.0% at five years and 88.2% at 10 years (p = 0.10, Tyrone-Ware). No risk factors for early and late mortality and reoperation were detected. CONCLUSION: In this combined series, the Ross operation in adult patients resulted in excellent survival and acceptable reoperation rates. A prospective randomized trial is proposed to study whether this observation truly reflects the potential advantages of the Ross procedure, or whether it is caused by patient selection.

Adult↗
PubMed2005

Pharmacological modulation of the hyperpolarization-activated current (I f) in human atrial myocytes: focus on G protein-coupled receptors.

AIMS: In human atrial myocytes (HuAM) two beta-adrenergic receptors (beta-AR) and four splicing-variants of the serotonin 5-HT(4) receptor are present. Multiple coupling with G stimulatory (G(s)) and G inhibitory (G(i)) proteins has been proposed for both beta(2)-AR and 5-HT((4b)) subtypes, but no functional data exist in HuAM. Serotonin (5-HT) and catecholamines are able to trigger arrhythmias in human atrium, but the underlying cellular mechanisms are not completely understood. The pacemaker current (I(f)) is an inward Na(+)/K(+) current, constitutively present in HuAM and directly modulated by cAMP; I(f) could play a role in triggering human atrial arrhythmias. This study evaluated the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors by assessing the modulation of I(f) by selective stimuli. METHODS: HuAM were isolated from right atrial appendages and utilized for patch-clamp recording. The coupling of receptor subtypes with G(i) proteins was tested by incubating HuAM in pertussis toxin (PTX). RESULTS: Beta(1)-AR stimulation (Isoprenaline [ISO] + ICI 118,551), and 5-HT caused a concentration-dependent significant shift of the half activation potential of I(f) activation curve (DeltaV(h)), P < 0.01. beta(2)-AR stimulation (ISO 1 microM + CGP 20712A) also significantly shifted V(h) (P < 0.0001), but with DeltaV(h)[beta(2)-AR] significantly smaller than the effect caused by 1 microM beta(1)-AR stimulation (P < 0.05). Pre-treatment of HuAM with PTX did not alter the effect of beta(1)-AR stimulation (both 0.1 and 1 microM) and 1 microM 5-HT on I(f), but significantly increased the effect in response to beta(2)-AR stimulation and 0.1 microM 5-HT (P < 0.05 for both), thus suggesting a G(i) protein coupling of these receptors. CONCLUSIONS: Our results provide the first functional evidence of the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors in HuAM. Further they support the view that I(f) current might play an important role in triggering catecholamines and serotonin-induced atrial arrhythmias.

Aged↗
PubMed2004

Atrial natriuretic peptide modulates the hyperpolarization-activated current (If) in human atrial myocytes.

OBJECTIVES: The relationship between atrial stretching and changes in cell excitability is well documented. Once stretched, human atrial myocytes (HuAM) release atrial natriuretic peptide (hANP). Receptors for hANP (NPR) are coupled to a guanylyl cyclase (GC) activity, and are present on HuAM, but the electrophysiological effects of hANP are largely unknown. We investigated the effect of hANP on If, the hyperpolarization-activated current present in HuAM, and the underlying intracellular pathway. METHODS: HuAM were isolated from atrial appendages and utilized for patch-clamp recording. RESULTS: hANP caused a significant and concentration dependent shift of the midpoint activation potential (DeltaVh) toward less negative potentials of 6.9 +/- 1.0 mV at 0.1 nM; 13.0 +/- 2.6 mV at 1 nM and 15.3 +/- 2.2 mV at 10 nM (p < 0.001 for all); a parallel increase of If rate of activation occurred. The effect of hANP was completely blocked by isatin, a potent antagonist of NPR (p < 0.01 vs. hANP). In the presence of the inhibitors of guanylyl cyclase (ODQ and LY83583), hANP caused a significantly smaller DeltaVh (p < 0.01 vs. hANP for both). 8Br-cGMP mimicked the effect of hANP, both in the presence and absence of KT5823, a selective inhibitor of Protein kinase G. Pretreatment with pertussis toxin (PTX) did not change the effect of hANP, thus excluding a major role for the coupling of NPR with the Gi-Proteins system. Pretreating cells with cyclopentyladenosine (CPA), an A1-adenosine receptor agonist, completely blocked hANP effect. Adding hANP to maximal serotonin concentration produced an additive response. CONCLUSIONS: Our data demonstrate for the first time that ANP is able to increase If, likely through a modulation of intracellular cGMP and cAMP levels. This effect could have implications in the relationship between stretch and arrhythmogenesis in the human atrium.

Adenosine↗
PubMed2004

The "elephant trunk" technique made easier.

In patients with diffuse aneurysmal disease, the "elephant trunk" technique, which uses surplus intravascular graft length to facilitate subsequent operations on the downstream aorta, is an accepted method of treatment. Nevertheless, in the presence of large aneurysms without a definite neck beyond the left subclavian artery, there is an increased risk of rupture at the level of the distal anastomosis. My colleagues and I herein describe a modified elephant trunk technique performed with a new prosthesis, which was conceived to overcome the difficulties and the risks inherent in a large aneurysmal neck.

Aged↗
PubMed2004

Residual dissection of the brachiocephalic arteries: significance, management, and long-term outcome.

OBJECTIVES: Residual dissection of the brachiocephalic arteries after operations for acute type A dissection is considered a benign condition that does not expose patients to late neurologic events. This retrospective study, conducted on an outpatient clinic basis between June 1995 and May 2003, had the objectives of evaluating the consequences of residual dissection of the brachiocephalic arteries, investigating the long-term outcomes of patients with this condition, and illustrating our approach to the condition. METHODS: Forty-two of 137 patients with spontaneous aortic dissection were identified as having residual dissection of the brachiocephalic arteries. There were 30 men and 12 women, with median age of 64.8 years. Patients were followed for a median time of 3.17 years (25th-75th percentile, 1.43-4.40 years; maximum, 7.5 years). The main outcome was the occurrence of cerebral ischemic events (transient ischemic attack or stroke) or death. The functional consequences of brachiocephalic artery dissection were studied by using duplex scanning and transcranial Doppler ultrasonography. RESULTS: Twenty-four focal neurologic complications occurred in 13 of 42 patients (incidence, 30.9%); major strokes occurred in 6 patients, and none were fatal. Minor strokes occurred in 12 patients. In all patients the damaged territory was dependent on a dissected artery. Kaplan-Meier (90-months) freedom from focal neurologic events was 55.7% (95% confidence interval, 33.7%-72.9%). Mean time of freedom from focal neurologic events was 64.5 months (95% confidence interval, 53.1-75.9 months). Positive transcranial Doppler monitoring for microembolic signals was 24.1%, and patients with clinical symptoms had higher microembolic signal counts than did those without symptoms (8.4/h vs 1.9/h, P <.001). Reduced cerebrovascular reactivity to hypercapnia, calculated by using the breath-holding index values, was associated with severely impaired brachiocephalic artery perfusion. The multivariable model for predictors of late stroke (minor and major) included the following variables: microembolic signal count (1 signal/h increase; relative risk, 1.27 [95% CI, 1.12-1.77]), breath-holding index (0.10 increase; relative risk, 0.91 [95% CI, 0.87-0.94]), and the presence of at least one carotid axis with a thrombosed false channel (relative risk, 0.82 [95% CI, 0.64-0.93]). Sixteen operations were performed in 12 patients to relieve residual dissection. CONCLUSIONS: These results suggest an increased risk of ischemic events ipsilateral to the dissected arteries. Strict follow-up and identification of subjects at risk implies the exact knowledge of vessel anatomy and perfusion status. Ultrasonographic transcranial Doppler examination plays an important role in the clinical work-up of these patients.

Aged↗
PubMed2003

Phenotypic variability of cardiovascular manifestations in Marfan Syndrome. Possible role of hyperhomocysteinemia and C677T MTHFR gene polymorphism.

AIMS: The aim of this study was to evaluate (1) homocysteinemia and the prevalence of the C677T MTHFR polymorphism in Marfan patients and (2) whether the severity of cardiovascular manifestations is associated with homocysteinemia and/or C677T polymorphism. METHODS AND RESULTS: We studied 107 patients subdivided into three subgroups based on the severity of cardiovascular manifestations: (A) no involvement (n=4); (B) mild involvement (n=45); (C) aortic dilatation or aortic dissection (n=58), and 189 controls. Total homocysteine (tHcy) was significantly higher in subgroup C than in subgroup B. In subgroup C patients with dissection tHcy was higher than in those without dissection. In subgroup C the prevalence of 677T homozygotes was higher, but not significantly, than in the subgroup B. In patients with dissection the prevalence of 677T homozygotes was significantly higher than in those without dissection and than in subgroup B. In the logistic regression analysis, severe cardiovascular manifestations and aortic dissection in Marfan patients were associated with tHcy plasma levels. CONCLUSIONS: Our data indicate an association between the severity of the cardiovascular manifestations, in particular aortic dissection, and elevated tHcy levels. This suggests an important role for tHcy in determining phenotypic variability in Marfan patients and provides further evidence for the association of homocysteinemia with the damage of the vascular system.

Adolescent↗
PubMed2003

In situ retrocaval skeletonized right internal thoracic artery anastomosed to the circumflex system via transverse sinus: technical aspects and postoperative outcome.

BACKGROUND: The aim of this study was to investigate whether, by using the in situ right internal thoracic artery via the transverse sinus (eventually retrocaval), both the proximal and distal major branches of the circumflex system could be grafted and to evaluate the early and late outcome in these patients. METHODS: Between January 1997 and March 2002, 452 consecutive patients underwent grafting of the circumflex system with the in situ skeletonized right internal thoracic artery routed via the transverse sinus. The mean age was 62.4 +/- 10.3 years. A mean of 2.2 +/- 0.3 arterial grafts per patient were used, and 271 (60%) patients underwent total arterial myocardial revascularization. At 3 months after surgery, 86 patients (right Y or T graft) underwent echo color Doppler imaging before and after an adenosine provocative test. The mean follow-up was 27 +/- 8 months. RESULTS: The success rate of skeletonized right internal thoracic artery grafting to the circumflex system branch was 100%. There were 15 (3.4%) hospital deaths. In 116 patients who underwent postoperative angiography, the total patency rates of the right and left internal thoracic arteries were 94% and 96.6%, respectively. Strong predictors for nonfunctional internal thoracic artery grafts were a small internal thoracic artery caliber (P <.001), recipient coronary artery diameter less than 1.5 mm (P =.012), stenotic lesions of less than 60% (P =.016), and diffuse stenotic lesions (P =.015) of the recipient coronary artery. In 86 patients who underwent postoperative echo color Doppler imaging, the flow reserves at the main stem of the left and right internal thoracic arteries were 2.24 +/- 0.5 and 2.48 +/- 0.6, respectively. Cumulative actuarial survival at 3 years was 96.3%, and event-free cumulative survival was 93%. The Cox model revealed a left ventricular ejection fraction of less than 35% (P =.016), age greater than 70 years (P =.025), New York Heart Association grade greater than III (P =.0019), nontotal arterial myocardial revascularization (P =.002), and the preoperative presence of more than 1 ischemic area (P <.001) as strong predictors for poor overall cumulative event-free survival. CONCLUSIONS: The skeletonized right internal thoracic artery, placed via the transverse sinus and eventually retrocaval, can reach most branches of the circumflex system and is associated with an excellent patency rate. The predictors for poor overall event-free survival seem to be similar to those of the general population undergoing conventional coronary artery bypass grafting. Use of bilateral internal thoracic arteries and in situ right internal thoracic artery grafting via the transverse sinus offers the possibility of various configuration constructions, making possible total arterial myocardial revascularization with a minimum number of arterial conduits.

Adult↗
PubMed2002

Does ministernotomy improve postoperative outcome in aortic valve operation? A prospective randomized study.

BACKGROUND: The aim of this study was to compare the postoperative outcome obtained in patients undergoing elective aortic valve operation, either through ministernotomy or conventional sternotomy. METHODS: Between January 1999 and July 2001, 80 consecutive patients undergoing elective aortic valve replacement were randomly divided into two groups: group I (n = 40 patients) undergoing a ministernotomy approach (reversed-C or reversed-L), and group II (n = 40 patients) undergoing conventional sternotomy. RESULTS: The length of skin incision was significantly shorter in group I than in group II (8.2+/-1.3 cm versus 23.7+/-2.6 cm, p < 0.001). No significant differences were found in cardiopulmonary bypass duration, associated procedures, or aortic cross-clamping times. Total operating time was 3.7+/-0.46 hours in group I compared with 3.4+/-0.6 hours in group II (p = 0.014). A similar incidence of cardiac, neurologic, infective, and renal complications between groups was found. Mean mediastinal drainage and mean blood transfusions (amount of blood transfused) per patient were greater in group II (p < 0.004 and p < 0.001, respectively). Twenty-five (62.5%) patients in group II and 15 (37.5%) patients in group I required postoperative blood transfusion (p = 0.04). Mechanical ventilation time was significantly longer in group II (6.2+/-1.8 hours versus 4.4+/-0.9 hours, p = 0.006). Five days after the surgical procedure, spirometric data analysis demonstrated a significantly lower total lung capacity and maximum inspiratory and expiratory pressures in group II compared with group I (p = 0.003, p = 0.007, and p < 0.001, respectively). CONCLUSIONS: Our results showed that ministernotomy had not only important cosmetic advantages but also beneficial effects in blood loss and transfusion, postoperative pain, and probably in sternal stability. Ministernotomy also improved recovery of respiratory function and allowed earlier extubation and hospital discharge.

Aged↗
PubMed2002

Early and long-term outcome in patients undergoing aortic root replacement with composite graft according to the Bentall's technique.

OBJECTIVE: The aims of this study were: (i) to evaluate the early and long-term outcome in patients undergoing aortic root replacement (ARR) with a composite graft; (ii) to identify the predictors for poor overall survival in this pool of patients. MATERIAL AND METHODS: Between January 1989 and December 2000, 212 patients underwent ARR with a CG. Mean age was 56+/-14 years, ranging from 16 to 77. Annuloaortic ectasia was the most frequent cause of aortic disease in this series, 81 (38%) patients, followed by atherosclerotic aneurysm 57 (27%) and type A acute aortic dissection 52 (24.5%). Marfan's syndrome was present in 37 (17.5%) patients. Duration of follow-up ranged from 1 to 120 months, mean 59+/-35 months. RESULTS: The overall hospital mortality was 16 (7.5%) patients. Eight of them had aortic dissection and four Marfan syndrome. The most frequently found complication resulted to be renal failure in 22 (10%) patients and low cardiac output in 15 (7%) patients. The incidence of perioperative myocardial infarction, neurological complications, respiratory complications, renal failure and coagulopathy incidence were significantly higher in patients with cardiopulmonary bypass (CPB) time >170 min, CA >40 min, and total aortic arch replacement. The actuarial survival at 1, 3 and 5 years resulted to be 91.8, 86 and 81.5%, instead the actuarial survival without re-operation resulted to be 89, 82 and 78%. The actuarial survival in patients with aortic dissection was significantly lower versus non-dissection (P=0.022). The multivariate analysis revealed the aortic dissection (P=0.03), age >65 years (P=0.014), associated coronary artery disease (P=0.002), NYHA functional class>/=3 (P=0.027), LVEF <35% (P=0.002) and total arch reconstruction (P=0.003) as strong predictors for poor overall survival in patients undergoing ARR. CONCLUSIONS: The ARR with a CG offers acceptable early and long-term outcome. The predictors for poor overall survival in patients undergoing ARR seems to be preoperative aortic dissection extended into the aortic arch, older age, depressed left ventricular function and associated coronary artery disease.

Adolescent↗
PubMed2002

Early postoperative outcome and hemodynamic performance of the sorin pericarbon stentless aortic valve.

BACKGROUND AND AIMS OF THE STUDY: Stentless aortic bioprostheses offer potential advantages in terms of durability and hemodynamic performance. The study aim was to evaluate the early postoperative performance of the Sorin Pericarbon stentless bioprosthesis. METHODS: Between November 1999 and December 2000, 34 patients (12 males, 22 females; mean age 71.2 +/- 4.8 years; range: 48-85 years) underwent aortic valve (AV) replacement with the Sorin Pericarbon stentless bioprosthesis. Twenty-two patients were in NYHA classes III-IV, and 12 were in classes I-II. Twenty-one patients had AV stenosis, nine AV regurgitation, and four mixed pathology. Doppler-echocardiography was performed before surgery, at hospital discharge and at six-month follow up. At this time, 20 patients also underwent echo-Doppler stress testing, with peak transvalvular gradient measured at rest and during exercise. RESULTS: There were two hospital deaths (not valve-related). No significant perioperative complications were recorded. At hospital discharge, the aortic peak gradient was 15.7 +/- 10.6 mmHg; nil or trivial aortic regurgitation was found in three patients. During six months follow up no endocarditis or thromboembolic events were registered. At six months postoperatively, the transvalvular peak gradient showed a small but significant decrease (11.3 +/- 3.5 mmHg at six months, p = 0.036). Mean left ventricular mass index was also decreased significantly (118.4 +/- 28.5 versus 98.4 +/- 17.8 g/m2, p = 0.024). Left ventricular ejection fraction and effective orifice area were not changed significantly during follow up. In patients undergoing exercise testing (mean maximal workload 96 +/- 48 W), the peak aortic gradient was increased (not significantly) at exercise peak (from 14.7 +/- 6.5 to 17.2 +/- 6.7 mmHg, p = 0.086). CONCLUSION: The excellent early postoperative outcome of this experience with the Sorin Pericarbon stentless valve encourages the use of this prosthesis. Long-term follow up and further evaluations are required with regard to hemodynamic performance and durability.

Aged↗
PubMed2002

[Ministernotomy improves the postoperative course in aortic valve replacement].

BACKGROUND: The advantages and the safety aspects of ministernotomy, in aortic valve replacement, are presently under investigation. The aim of this study was to compare the postoperative results between ministernotomy access and standard total sternotomy access. METHODS: Between January 1997 and July 2002, 98 patients underwent elective aortic valve replacement. They were divided into two groups: group Gm (49 patients) undergoing a ministernotomy approach ("reversed C" or "reversed L") and group Gs (49 patients) undergoing conventional total sternotomy. RESULTS: The length of the skin incision was significantly shorter in group Gm (p < 0.001). The total operative time was significantly longer in group Gm (p = 0.02), but no significant differences were found in the cardiopulmonary bypass and aortic cross-clamping times. Mean mediastinal drainage, incidence of bleeding > 800 ml, mechanical ventilation time, intensive care unit stay and hospital stay were significantly greater in group Gs. Five days after the surgical procedure, spirometric analysis demonstrated a significant reduction in total lung capacity, and in maximum expiratory and inspiratory pressures in group Gs compared with group Gm (p = 0.003, p = 0.001, p = 0.01, respectively). CONCLUSIONS: Our results showed that in addition to cosmetic advantages, ministernotomy is also associated with a better outcome in terms of sternal stability, blood loss and transfusions, and postoperative pain. Ministernotomy also improved the recovery of respiratory function, with a shorter mechanical ventilation time and allowed an earlier hospital discharge.

Aortic Valve↗
PubMed2001

Search for Chlamydia pneumoniae genes and their expression in atherosclerotic plaques of carotid arteries.

Samples of atherosclerotic tissue from 58 patients undergoing carotid surgery were analysed by tissue culture and PCR for Chlamydia pneumoniae; PCR was performed to detect Omp1, 16S rRNA and HSP-70 genes. To understand the active pathogenic role of C. pneumoniae, a reverse transcriptase-PCR (RT-PCR) assay was applied to detect the specific RNAs expressed either in the replicative form, or in the cryptic form found in chronic infection. The C. pneumoniae omp1 gene, encoding the major outer-membrane protein (MOMP), was detected in 13 of 58 samples. Among these, the result was confirmed in 11 samples after amplification of a further target, the 16S rRNA, and the presence of the HSP-70 gene, encoding heat-shock protein 70, was revealed in only five cases. All the samples were negative for evidence of specific RNAs by RT-PCR. The presence of genomic DNA and absence of specific RNAs in atherosclerotic tissue samples suggests a lack of an active metabolic or persistent infective role for C. pneumoniae. Thus, traces of C. pneumoniae DNA in these samples could be due to a degradative pathway of the host defensive cellular and biochemical mechanisms.

Adult↗