Luigi Lovato

Complicated Acute Type B Dissection: Is Surgery Still the Best Option?: A Report From the International Registry of Acute Aortic Dissection

OBJECTIVES Impact on survival of different treatment strategies was analyzed in 571 patients with acute type B aortic dissection enrolled from 1996 to 2005 in the International Registry of Acute Aortic Dissection. BACKGROUND The optimal treatment for acute type B dissection is still a matter of debate. METHODS Information on 290 clinical variables were compared, including demographics; medical history; clinical presentation; physical findings; imaging studies; details of medical, surgical, and endovascular management; in-hospital clinical events; and in-hospital mortality. RESULTS Of the 571 patients with acute type B aortic dissection, 390 (68.3%) were treated medically, 59 (10.3%) with standard open surgery and 66 (11.6%) with an endovascular approach. Patients who underwent emergency endovascular or open surgery were younger (mean age 58.8 years, p < 0.001) than their counterparts treated conservatively, and had male preponderance and hypertension in 76.9%. Patients submitted to surgery presented with a wider aortic diameter than patients treated by interventional techniques or by medical therapy (5.36 +/- 1.7 cm vs. 4.62 +/- 1.4 cm vs. 4.47 +/- 1.4 cm, p = 0.003). In-hospital complications occurred in 20% of patients subjected to endovascular technique and in 40% of patients after open surgical repair. In-hospital mortality was significantly higher after open surgery (33.9%) than after endovascular treatment (10.6%, p = 0.002). After propensity and multivariable adjustment, open surgical repair was associated with an independent increased risk of in-hospital mortality (odds ratio: 3.41, 95% confidence interval: 1.00 to 11.67, p = 0.05). CONCLUSIONS In the International Registry of Acute Aortic Dissection, the less invasive nature of endovascular treatment seems to provide better in-hospital survival in patients with acute type B dissection; larger randomized trials or comprehensive registries are needed to access impact on outcomes.

Non-invasive evaluation of the myocardial substrate of cardiac amyloidosis by gadolinium cardiac magnetic resonance

Objective: To investigate the prevalence and distribution of gadolinium (Gd) enhancement at cardiac magnetic resonance (CMR) imaging in patients with cardiac amyloidosis (CA) and to look for associations with clinical, morphological, and functional features. Patients and design: 21 patients with definitely diagnosed CA (nine with immunoglobulin light chain amyloidosis and 12 transthyretin related) underwent Gd-CMR. Results: Gd enhancement was detected in 16 of 21 (76%) patients. Sixty six of 357 (18%) segments were enhanced, more often at the mid ventricular level. Transmural extension of enhancement within each patient significantly correlated with left ventricular (LV) end systolic volume (r  =  0.58). The number of enhanced segments correlated with LV end diastolic volume (r  =  0.76), end systolic volume (r  =  0.6), and left atrial size (r  =  0.56). Segments with > 50% extensive transmural enhancement more often were severely hypokinetic or akinetic (p  =  0.001). Patients with > 2 enhanced segments had significantly lower 12 lead QRS voltage and Sokolow-Lyon index. No relation was apparent with any other clinical, morphological, functional, or histological characteristics. Conclusion: Gd enhancement is common but not universally present in CA, probably due to expansion of infiltrated interstitium. The segmental and transmural distribution of the enhancement is highly variable, and mid-ventricular regions are more often involved. Enhancement appears to be associated with impaired segmental and global contractility and a larger atrium.

A pilot study on the effects of carvedilol on right ventricular remodelling and exercise tolerance in patients with systemic right ventricle

BACKGROUND Patients with atrial repair for transposition of the great arteries and patients with congenitally corrected transposition have a right ventricle (RV) in the systemic position and they may develop RV dysfunction and exercise intolerance with advancing age. No data is available on the effect of carvedilol in patients with dysfunctional systemic RV. METHODS We studied with cardiovascular magnetic resonance (CMR), cardiopulmonary exercise testing, and standard 12-leads electrocardiogram, 8 adults (median age 26 years, range 18-31) with chronic stable heart failure and systemic RV dysfunction (6 patients with atrial repair and 2 patients with congenitally corrected transposition). Assessment was done before and after 12 months of carvedilol administration. The initial dose was 3.125 mg twice daily, and the target dose was 25 mg twice a day. RESULTS Carvedilol administration was safe and the target dose was achieved in 5/8 (62%) patients. Right ventricular end-diastolic (119 ± 31 vs. 112 ± 28 ml/m², p=0.01) and end-systolic volumes decreased (79 ± 17 vs. 65 ± 14 ml/m², p=0.006), and RV ejection fraction improved (34 ± 6 vs. 42 ± 7%, p=0.004). Left ventricular ejection fraction increased (44 ± 8 vs. 49 ± 9%, p=0.01), suggesting a positive biventricular remodelling. Peak oxygen uptake did not change with carvedilol (26.8 ± 5.3 vs. 27.3 ± 5.7 ml O₂/Kg/min, p=0.58), whereas exercise duration increased (13.4 ± 2.6 vs. 17.3 ± 3.1 min, p=0.008). CONCLUSIONS In this small cohort, carvedilol administration was safe and it was associated with positive RV remodelling as well as improved exercise duration.

Extension of dissection in stent-graft treatment of type B aortic dissection: lessons learned from endovascular experience.

Endovascular treatment is becoming the most important treatment modality in the complex management of type B dissection, providing benefits to both acute and chronic patients. Growing technical experience and improving stent-graft devices have resulted in better patient outcome and expanded clinical indications. Nevertheless, similar to any treatment option, this less invasive method has its inherent risks. Several cases of iatrogenic dissection have been reported in the literature, underlying the need for guidelines to minimize this risk and improve procedural safety. Extension of the dissection after endovascular repair of type B dissection does not appear to be device-specific, but related primarily to aortic wall alterations or adverse anatomy that arise most frequently in hypertensive patients or those with challenging aortic configuration. An accurate examination of the aortic wall and dissection anatomy and careful intraprocedural device manipulation and balloon molding may help avoid this potentially life-threatening complication.

Significance of Magnetic Resonance Imaging in Apical Hypertrophic Cardiomyopathy

Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of nonobstructive HC with peculiar characteristics. The investigators report a series of 13 consecutive Caucasian patients with a suspicion or diagnosis of apical HC on the basis of electrocardiographic and/or echocardiographic findings who prospectively underwent magnetic resonance imaging with late gadolinium enhancement (LGE) evaluation. All but 1 patient presented T-wave inversion in the anterolateral leads on electrocardiogram, with a mean maximum negative T wave of 7.0 +/- 3.9 mm. Echocardiography provided correct diagnoses in 9/13 patients (69%), while in 4 patients echocardiographic results were normal or inconclusive. Magnetic resonance imaging showed a spadelike morphology of the left ventricle in 6 patients and identified an apical aneurysm in 4. Eleven patients (85%) presented LGE with a mean percentage of 2.3 +/- 2.6% of total left ventricular mass. In 9 (69%) patients LGE was limited to the hypertrophic segments while in 6 (46%) patients it was also present in nonhypertrophic segments. In conclusion, magnetic resonance imaging in patients with apical HC showed a high incidence of apical aneurysms and a peculiar distribution of LGE, that was not limited to hypertrophic segments.

Role of endovascular repair in the management of late pseudo-aneurysms following open surgery for aortic coarctation

BACKGROUND Coarctation of the aorta accounts for almost 5% of all congenital cardiac malformations, and it is usually treated by open surgical procedures. Despite the excellent primary results, many patients may develop anastomotic pseudo-aneurysms, associated with considerable morbidity and mortality rates. We investigated the role of endovascular repair as an alternative to open re-do surgery on the descending aorta. METHODS We retrospectively collected data of 11 consecutive patients who presented with pseudo-aneurysms of the descending aorta following previous surgical repair of congenital aortic coarctation. Nine patients developed a pseudo-aneurysm after patch aortoplasty, while an interposition graft repair was performed in two cases. Seven patients underwent an endovascular repair (26.9 years after the previous open surgery). Four patients with a pseudo-aneurysm after coarctation repair associated with arch hypoplasia underwent conventional open re-operation. RESULTS No complications or death were observed in the conventional surgical group. Technical success was obtained in all patients who received a stent-graft procedure. More than one stent graft was necessary only in one case. A left carotid-left subclavian artery bypass was performed in three patients. Type II endoleak was detected by angiography in one patient who had previously undergone subclavian re-vascularisation. The median follow-up (FU) was 44.5 months and was 100% complete. Neither re-operations nor complications or deaths occurred during FU. CONCLUSIONS Endovascular repair of pseudo-aneurysms following open surgery for aortic coarctation is feasible and safe. However, more patients and longer follow-up are necessary to assess the efficacy of this promising less-invasive alternative to open re-do surgery.

Clinical value of multidetector CT coronary angiography as a preoperative screening test before non-coronary cardiac surgery

Objective: Myocardial scintigraphy and/or conventional angiography (CA) are often performed before cardiac surgery in an attempt to identify unsuspected coronary artery disease which might result in significant cardiac morbidity and mortality. Multidetector CT coronary angiography (MDCTCA) has a recognised high negative predictive value and may provide a non-invasive alternative in this subset of patients. The aim of this study was to evaluate the clinical value of MDCTCA as a preoperative screening test in candidates for non-coronary cardiac surgery. Methods: 132 patients underwent MDCTCA (Somatom Sensation 16 Cardiac, Siemens) in the assessment of the cardiac risk profile before surgery. Coronary arteries were screened for ⩾50% stenosis. Patients without significant stenosis (Group 1) underwent surgery without any adjunctive screening tests while all patients with coronary lesions ⩾50% at MDCTCA (Group 2) underwent CA. Results: 16 patients (12.1%) were excluded due to poor image quality. 72 patients without significant coronary stenosis at MDCTCA were submitted to surgery. 30 out of 36 patients with significant (⩾50%) coronary stenosis at MDCTCA and CA underwent adjunctive bypass surgery or coronary angioplasty. In 8 patients, MDCTCA overestimated the severity of the coronary lesions (>50% MDCTCA, <50% CA). No severe cardiovascular perioperative events such as myocardial ischaemia, myocardial infarction or cardiac failure occurred in any patient in Group 1. Conclusions: MDCTCA seems to be effective as a preoperative screening test prior to non-coronary cardiac surgery. In this era of cost containment and optimal care of patients, MDCTCA is able to provide coronary vessel and ventricular function evaluation and may become the method of choice for the assessment of a cardiovascular risk profile prior to major surgery.

Magnetic Resonance Imaging Evaluation of Aortic Elastic Properties as Early Expression of Marfan Syndrome

In Marfan syndrome, early identification and treatment of aortic involvement could improve prognosis, but clinical diagnosis may be difficult at a young age, before aortic dilation occurs. The aim of this study was to evaluate biomechanical aortic properties in Marfan patients and in their relatives to identify an early index of aortic involvement. A magnetic resonance imaging (MRI) morphologic and functional study of the thoracic aorta was performed in 20 Marfan patients, 15 family members, and 14 healthy volunteers as a control group. The aorta was imaged in the oblique sagittal plane by spin-echo sequence. A high-resolution gradient-echo sequence was then applied in the axial plane at the level of ascending supravalvular aorta to evaluate aortic distensibility. Aortic distensibility (mm Hg(-1) was significantly different in the three groups (ANOVA, p = 0.0001). Aortic distensibility was sensibly reduced in Marfan patients (0.0085 +/- 0.006 vs. 0.025 +/- 0.006 control group, p < 0.05). No significant correlation was found between aortic area and distensibility. Aortic distensibility was reduced also in family members (0.016 +/- 0.011 vs. 0.025 +/- 0.006 control group, p < 0.05). Among them, 4 subjects showed aortic diameters to the upper limit of the normal range, whereas the other 11 presented normal aortic diameters. Intraobserver and interobserver reproducibility for diastolic measurement was 1.2% and 0.4%, respectively, and 1.1% and 0.3%, respectively, for systolic measurement. MRI is an accurate technique in detecting abnormal aortic elastic properties in Marfan patients. Abnormal ascending aorta distensibility may constitute an index of early aortic involvement before dilation occurs.

New pathological insights into cardiac amyloidosis: implications for non-invasive diagnosis.

Background: Knowledge of the patterns of myocardial amyloid accumulation could improve the interpretation of electrocardiographic, echocardiographic and magnetic resonance imaging findings of amyloidosis. We assessed the extent and pattern of myocardial amyloid infiltration in explanted or autopsied hearts of patients with cardiomyopathy related to acquired monoclonal immunoglobulin light-chain (AL) or hereditary transthyretin (TTR) related amyloidosis (ATTR). Methods: We analyzed nine explanted/autopsied hearts from patients with AL (n = 4) and ATTR (n = 5) cardiac amyloidosis. For each heart, a biventricular histological macrosection was obtained at mid-ventricular level and analyzed with both inspective and computer-assisted histologic and histomorphometric analysis aimed in particular at quantifying muscle cells, fibrosis and amyloid infiltration. Results: The extent of amyloid infiltration of the left ventricle (LV) ranged from 45 to 76% (median [interquartile range (IQR)] = 57% [51–64]) of the overall surface. Although LV trabecular and subendocardial were the most infiltrated layers (45–94%, median [IQR] = 73% [67–84] and from 44 to 71%, median [IQR] = 57% [49–59], respectively), intra- and inter-patient heterogeneity was high. Three main patterns of amyloid infiltration of the LV were identified: diffuse (five cases), mainly subendocardial (two cases), and mainly segmental (two cases). The extent of amyloid infiltration of the right ventricle ranged from 48 to 93% (median [IQR] = 61% [59–83]); contributions of parietal and trabecular layers ranged from 32 to 99% (median [IQR] = 63% [47–88]) and from 49 to 93% (median [IQR] = 74% [64–79]), respectively. Conclusions: In amyloidotic cardiomyopathy, amyloid deposition is highly heterogeneous. Different patterns of infiltration are identifiable, including diffuse, mainly segmental and mainly subendocardial. Awareness of this variability can help the interpretation of ECGs, echocardiograms and magnetic resonance imaging.

Endovascular treatment for acute traumatic transection of the descending aorta: Focus on operative timing and left subclavian artery management

OBJECTIVE The operative timing and management of acute traumatic aortic rupture are matters of debate. We reviewed our experience with endovascular repair of acute traumatic aortic rupture, focusing on these topics. METHODS From 1998 to 2007, 31 patients were referred to our institute for acute traumatic rupture of the descending aorta. In 11 patients (group I) an early stent graft procedure was performed, whereas in 16 patients (group II) endovascular repair was delayed. The median time from trauma was 24 hours in group I and 1.5 months in group II. Eight (25.8%) patients had a short proximal neck (<5 mm from the left subclavian artery). Of these, 2 had the left subclavian artery totally covered by the endoprosthesis, and 2 had the left subclavian artery partially covered. Four patients with a posttraumatic pseudoaneurysm involving the left subclavian artery (3 patients) or the left common carotid artery (1 patient) underwent conventional open surgical intervention. RESULTS Technical success was obtained in all patients. There were neither intraoperative nor perioperative deaths. Cerebellar stroke was detected in 1 patient after the intentional closure of the left subclavian artery. Follow-up (32.7 +/- 27.5 months) was 100% complete. No late deaths, endoleaks, or complications occurred. CONCLUSION The endovascular approach was a safe and flexible procedure in traumatic aortic rupture and allowed us to fit the operative timing to every patients clinical and imaging findings. In the presence of an inadequate proximal landing zone, conventional open surgical intervention still remains a favorable option as an alternative to endovascular procedures if a surgical revascularization of the left subclavian artery, carotid artery, or both is necessary.