Lazzaro Paraggio

Reversible coronary microvascular dysfunction: a common pathogenetic mechanism in Apical Ballooning or Tako-Tsubo Syndrome

AIMS To study coronary microvascular dysfunction as possible pathogenetic mechanism in Apical Ballooning Syndrome (ABS). METHODS AND RESULTS Fifteen ABS patients (all women, 68 +/- 14 years) underwent myocardial contrast echocardiography at baseline during adenosine infusion (140 microg/kg/min) and at 1-month follow-up and compared with a group of anterior ST-elevation myocardial infarction (STEMI) patients with similar clinical characteristics. Myocardial perfusion was assessed by contrast score index (CSI) and endocardial length of contrast defect (contrast defect length, CDL), whereas myocardial dysfunction by wall motion score index (WMSI), endocardial length of contractile dysfunction (wall motion defect length, WMDL), and LV ejection fraction (LVEF). At baseline, no difference in myocardial perfusion and dysfunction were present between the two groups. During adenosine challenge, while no changes were observed in STEMI group, in ABS patients CSI, CDL, WMSI, and WMDL significantly decreased compared with baseline (P < 0.001 vs. baseline for all parameters) and LVEF significantly increased (P = 0.01 vs. baseline). At 1-month follow-up, myocardial perfusion and dysfunction completely recovered in ABS patients (P < 0.001 vs. baseline for all parameters), whereas no significant changes were observed in STEMI group. CONCLUSION Our data strongly suggest that in ABS, irrespectively of its underlying aetiology, acute and reversible coronary microvascular vasoconstriction could represent a common pathophysiological mechanism.

Characterization of microvascular and myocardial damage within perfusion defect area at myocardial contrast echocardiography in the subacute phase of myocardial infarction

AIMS The anatomical correlates of perfusion defect (PD) at myocardial contrast echocardiography (MCE) in the subacute phase of ST-elevation myocardial infarction (STEMI) are currently unknown. The study aimed at assessing whether, in the subacute phase of STEMI, within MCE PD microvessels are anatomically damaged or if some vasodilation can be still elicited and if the PD correlates with the extent of myocardial necrosis. METHODS AND RESULTS Twenty-two post-percutaneous coronary intervention (PCI) patients underwent MCE 7 ± 1 days after STEMI, at baseline and after adenosine (ADN) administration. An area of completely non-opacified myocardium, corresponding to the area of the PD, was quantitated by planimetry. The area of the PD on MCE was compared with biochemical and imaging measures of myocardial necrosis: cardiac Troponin T peak (cTnT peak) and hyperenhanced area at gadolinium-enhanced cardiac magnetic resonance (Gd-CMR), respectively. After vasodilator stimulus, the area of the PD remained significantly unchanged when compared with the baseline value (P = 0.09 vs. baseline). The MCE index correlated at baseline with cTnT peak and Gd-CMR assessments of myocardial necrosis (P < 0.001). Also after ADN infusion, correlations between PD and extent of myocardial necrosis were similar to that assessed at baseline. CONCLUSION When assessed in the subacute phase of STEMI, the extent of the PD on MCE represents an area of both myocardial and microvascular necrosis.

Influence of left ventricular hypertrophy on microvascular dysfunction and left ventricular remodelling after acute myocardial infarction

AIMS To ascertain whether the presence of left ventricular (LV) hypertrophy in patients with ST-segment elevation myocardial infarction (STEMI) influences microvascular dysfunction and LV remodelling at 6 months of follow-up. METHODS AND RESULTS Fifty-six consecutive STEMI patients successfully treated with primary or rescue percutaneous coronary intervention underwent conventional two-dimensional and myocardial contrast echocardiography within 24 h and at 6 months. Left ventricular mass, end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction, and wall motion score index (WMSI) were measured. Left ventricular hypertrophy was defined as LV mass index >116 g/m(2) in men and >104 g/m(2) in women. In order to evaluate the potential influence of microvascular dysfunction on LV remodelling, myocardial perfusion was semiquantitatively scored by contrast score index (CSI). Patients with LV hypertrophy had higher EDV and ESV both at 24 h and at 6 months, compared with patients without LV hypertrophy (P < 0.05). No significant changes over time were observed in both groups. Both WMSI and CSI were similar between groups at 24 h and at follow-up, but improved in both groups over time (P < 0.05). CONCLUSION Left ventricular hypertrophy does not appear to influence the development of post-acute myocardial infarction LV remodelling. Hypertrophic and non-hypertrophic left ventricles showed the same extent and temporal improvement in regional contractile function and microvascular perfusion.

Percutaneous transcatheter aortic valve replacement induces femoral artery shrinkage: Angiographic evidence and predictors for a new side effect

We sought to investigate the possible impact of transaortic valve replacement (TAVR) on common femoral artery (CFA) integrity as assessed by angiography.

Update on Provisional Technique for Bifurcation Interventions.

A series of scientific evidence supports the concept that provisional side-branch stenting should be the preferred strategy for percutaneous coronary intervention of bifurcation coronary lesions. However, to date, many interventional cardiologists still consider this technique unsuitable for complex bifurcation lesions. This is mainly due to the fact that provisional stenting may be performed in different ways and several technical refinements may influence the procedural outcome. We here systematically overviewed the arguments which should be considered during the following steps of the provisional strategy: branch wiring, side-branch predilation, “crossover” stenting, proximal optimization, kissing balloon and the side-branch rescue techniques. We suggest that provisional stenting should be regarded as a highly flexible technique which, with specific technical tricks, may allow us to safely treat patients with wide spectrum of bifurcated lesion complexity.

Positron Emission Tomography in Acute Coronary Syndromes

Several imaging techniques have been used to assess cardiac structure and function, to understand pathophysiology, and to guide clinical decision making in the setting of acute coronary syndromes (ACS). Over the last years, cardiac positron emission tomography (PET) has affirmed its role in this setting. Indeed, the combined quantitative assessment of myocardial metabolism and perfusion has allowed to better understand the functional status of infarcted and non-infarcted myocardium, thus improving our knowledge of myocardial response to necrosis. More recently, several studies, taking advantage of previous observations in patients with cancer, have shown that PET could also provide important information on the mechanisms of vascular instability through the early identification of activated inflammatory cells in the atherosclerotic plaque. These findings are opening the way to more effective forms of prevention of acute vascular syndromes in high-risk patients; furthermore, new more sensitive and specific tracers for the identification of vascular inflammation are under development. In this review, we describe the potential and limitations of PET in the assessment of ACS.

Multiple vertebral fractures precipitate a platypnea-orthodeoxia syndrome in a patient with atrial septal defect and aortic root dilatation: When the upright position becomes intolerable

Platypnea-orthodeoxia syndrome is a rare disease characterized by dyspnea and oxygen desaturation induced by the upright position and relieved by recumbency. We report a case of a 65-year-old woman with a recent history of traumatic hip and multiple vertebral fractures referred to our institute due to onset of severe acute dyspnea. Transthoracic and transesophageal echocardiography, conducted by intravenous administration of agitated saline contrast solution, revealed the presence of atrial septal defect (ASD) associated with an important bidirectional shunting that was right-to-left directed when the patient was in a sitting position. Surgical closure of ASD resulted in resolution of the syndrome.

Correlation between frequency-domain optical coherence tomography and fractional flow reserve in angiographically-intermediate coronary lesions

BACKGROUND The decision-making process of patients with angiographically-intermediate coronary lesions (ICL) is clinically challenging and may benefit from adjunctive invasive techniques. Fractional-flow-reserve (FFR) represents the gold standard to evaluate ICL but frequency-domain optical-coherence-tomography (OCT) is a novel, promising, high resolution coronary imaging technique, which allows physiopathologic assessment of coronary plaque. We investigated the possible relation between OCT and FFR in selected ICL patients. METHODS Stable or unstable patients with ICL who underwent both FFR and OCT assessment at two large tertiary centers were retrospectively enrolled. FFR was performed according to standard methodology. OCT images were (on blind to clinical and FFR results) analyzed to assess minimal lumen area (MLA), percentage area stenosis (AS), thrombus and plaque ulceration. RESULTS Forty patients were identified (62±10years, 93% symptomatic, 35% acute presentation, 93% left-anterior-descending artery ICL). Percentage diameter stenosis at quantitative coronary angiography was 40±12% and FFR was 0.85±0.07. MLA (p=0.009), AS (p<0.001) and plaque ulceration (p=0.02) were significantly associated with FFR values. An integrated assessment of AS (≥ or <70%), MLA (≥ or <2.5mm2) and presence or absence of thrombus and plaque ulceration was found to have the potential to accurately (sensitivity 91%, specificity 93%) predict FFR results. CONCLUSION In patients with ICL, a combination of different OCT parameters may help predict FFR results. These findings suggest that only a comprehensive assessment of lesion features by OCT can allow an accurate prediction of lesion severity assessed by FFR.

An update on radial approach for percutaneous coronary intervention in patients with chronic total occlusion

Radial approach is the emerging arterial access for percutaneous coronary interventions (PCIs) in patients with coronary artery disease. Among the different subset of complex targets for PCI, chronic total occlusion (CTO) still represent a challenge for the interventional cardiologist. Is radial approach suitable for PCI on CTO? A series of data collected in selected centers with high volume of transradial procedures supported the change from elective transfemoral approach to systematic transradial approach. In this paper, we tried to provide an update on the technical aspects and the theoretical data which may be useful during the planning of CTO procedures. Overall, a full knowledge of upper limb vascular anatomy, arterial sheaths/guiding catheters selections, transradial PCI technique and CTO lesion management skill is pivotal to safely offer CTO patients the potential benefit of reduced bleeding risks through radial access adoption.

Rapid-deployment or transcatheter aortic valves in intermediate-risk patients?

Background Transcatheter aortic valve implantation and rapid-deployment aortic valve replacement represent two emerging therapies for patients with intermediate surgical risk and severe aortic stenosis. However, head-to-head comparisons between such novel therapies are lacking. Methods Severe aortic stenosis patients with intermediate surgical risk treated with rapid-deployment valve replacement at our institution were identified and compared with a propensity-matched population of patients who underwent transcatheter aortic valve replacement. Postoperative echocardiographic findings, in-hospital and midterm clinical outcomes were compared. Results We identified 60 patients who received transcatheter (n = 30) or rapid-deployment (n = 30) valve replacement. On postoperative echocardiography, freedom from paravalvular regurgitation was higher in the rapid-deployment valve group (p < 0.001), while postoperative mean transprosthetic gradient was lower in the transcatheter valve group (p = 0.03). Permanent pacemaker implantation was required more frequently in transcatheter valve patients (p = 0.01). Postoperative atrial fibrillation was more common in the rapid-deployment valve group (p = 0.03). Hospital mortality was similarly low in both groups (p = 0.33). At midterm follow-up, mortality was comparable (p = 0.42) but the rapid-deployment valve group still had a lower degree of paravalvular regurgitation. Conclusions Transcatheter and rapid-deployment valve replacement are promising treatment options for patients with intermediate surgical risk. These two techniques are associated with specific patterns of prosthesis function and postoperative complications. Further evaluation of the clinical impact of these therapies in this patient population is needed.