Francesco Cappelli

Detection of significant coronary artery disease by noninvasive anatomical and functional imaging.

Background—The choice of imaging techniques in patients with suspected coronary artery disease (CAD) varies between countries, regions, and hospitals. This prospective, multicenter, comparative effectiveness study was designed to assess the relative accuracy of commonly used imaging techniques for identifying patients with significant CAD. Methods and Results—A total of 475 patients with stable chest pain and intermediate likelihood of CAD underwent coronary computed tomographic angiography and stress myocardial perfusion imaging by single photon emission computed tomography or positron emission tomography, and ventricular wall motion imaging by stress echocardiography or cardiac magnetic resonance. If ≥1 test was abnormal, patients underwent invasive coronary angiography. Significant CAD was defined by invasive coronary angiography as >50% stenosis of the left main stem, >70% stenosis in a major coronary vessel, or 30% to 70% stenosis with fractional flow reserve ⩽0.8. Significant CAD was present in 29% of patients. In a patient-based analysis, coronary computed tomographic angiography had the highest diagnostic accuracy, the area under the receiver operating characteristics curve being 0.91 (95% confidence interval, 0.88–0.94), sensitivity being 91%, and specificity being 92%. Myocardial perfusion imaging had good diagnostic accuracy (area under the curve, 0.74; confidence interval, 0.69–0.78), sensitivity 74%, and specificity 73%. Wall motion imaging had similar accuracy (area under the curve, 0.70; confidence interval, 0.65–0.75) but lower sensitivity (49%, P<0.001) and higher specificity (92%, P<0.001). The diagnostic accuracy of myocardial perfusion imaging and wall motion imaging were lower than that of coronary computed tomographic angiography (P<0.001). Conclusions—In a multicenter European population of patients with stable chest pain and low prevalence of CAD, coronary computed tomographic angiography is more accurate than noninvasive functional testing for detecting significant CAD defined invasively. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00979199.

Tissue Doppler and strain imaging: a new tool for early detection of cardiac amyloidosis.

Using traditional echocardiography, the diagnosis of cardiac amyloidosis (CA) is often only possible in advanced stage when recommended therapies may have adverse effects. The aim of our study was to evaluate whether additional information can be derived from Tissue and strain Doppler imaging (TDI and SDI). Forty patients with systemic amyloidosis and 24 healthy subjects underwent traditional, tissue and strain Doppler echocardiography. Patients were classified having CA if mean wall thickness (mT), was half of the sum septum and posterior wall thickness, was ≥12 mm. The following parameters were evaluated: peak early diastolic velocity (Em) as index of ventricular relaxation, mitral E-wave to Em ratio (E/Em) as index of left ventricular (LV) filling pressure and mean LV strain peak curves (mSt) as global long-axis contraction index. In non cardiac amyloidosis (NCA), both Em and mSt were lower than in age matched controls (p < 0.01, p < 0.05, respectively) and higher than in CA (p < 0.01 and p < 0.01, respectively). Both Em and mSt were related to mT (p < 0.001). A significant (p < 0.01) nonlinear relation was observed between plasma terminal of pro B-natriuretic peptide and mT, Em, E/Em and mSt. TDI and SDI are able to detect amyloid myocardial involvement in such an early stage that cannot be evidenced by using traditional echocardiography.

Comb-assisted subkilohertz linewidth quantum cascade laser for high-precision mid-infrared spectroscopy

We report on the linewidth narrowing of a room-temperature mid-infrared quantum cascade laser by phase-locking to a difference-frequency-generated radiation referenced to an optical frequency comb synthesizer. A locking bandwidth of 250 kHz, with a residual rms phase-noise of 0.56 rad, has been achieved. The laser linewidth is narrowed by more than 2 orders of magnitude below 1 kHz, and its frequency is stabilized with an absolute traceability of 2×10−12. This source has allowed the measurement of the absolute frequency of a CO2 molecular transition with an uncertainty of about 1 kHz.

Subkilohertz linewidth room-temperature mid-infrared quantum cascade laser using a molecular sub-Doppler reference

We report on the narrowing of a room-temperature mid-IR quantum cascade laser by frequency locking it to a CO2 sub-Doppler transition obtained by polarization spectroscopy. A locking bandwidth of 250 kHz has been achieved. The laser linewidth is narrowed by more than two orders of magnitude below 1 kHz, and its absolute frequency is stabilized at the same level.

Direct link of a mid-infrared QCL to a frequency comb by optical injection.

A narrow-linewidth comb-linked nonlinear source is used as master radiation to injection lock a room-temperature mid-infrared quantum cascade laser (QCL). This process leads to a direct lock of the QCL to the optical frequency comb, providing the unique features of narrow linewidth, absolute frequency, higher output power, and wide mode-hop-free tunability. The QCL reproduces the injected radiation within more than 94%, with a reduction of the frequency-noise spectral density by 3 to 4 orders of magnitude up to about 100 kHz, and a linewidth narrowing from a few MHz to 20 kHz.

A real-time three-dimensional echocardiographic validation of an intracardiac electrogram-based method for optimizing cardiac resynchronization therapy

Introduction: Although optimization of atrioventricular and interventricular delays has been demonstrated to improve hemodynamics in patients with cardiac resynchronization therapy (CRT), the required time‐consuming procedure discourages its use in clinical practice. Recently, a new method for CRT optimization based on the intracardiac electrogram (IEGM) detected by the implanted leads, has been developed. We evaluated the effectiveness of this method in improving left ventricular (LV) asynchrony and performance using real‐time 3D echocardiography (RT3DE).

Multicentre multi-device hybrid imaging study of coronary artery disease: results from the EValuation of INtegrated Cardiac Imaging for the Detection and Characterization of Ischaemic Heart Disease (EVINCI) hybrid imaging population

AIMS Hybrid imaging provides a non-invasive assessment of coronary anatomy and myocardial perfusion. We sought to evaluate the added clinical value of hybrid imaging in a multi-centre multi-vendor setting. METHODS AND RESULTS Fourteen centres enrolled 252 patients with stable angina and intermediate (20-90%) pre-test likelihood of coronary artery disease (CAD) who underwent myocardial perfusion scintigraphy (MPS), CT coronary angiography (CTCA), and quantitative coronary angiography (QCA) with fractional flow reserve (FFR). Hybrid MPS/CTCA images were obtained by 3D image fusion. Blinded core-lab analyses were performed for CTCA, MPS, QCA and hybrid datasets. Hemodynamically significant CAD was ruled-in non-invasively in the presence of a matched finding (myocardial perfusion defect co-localized with stenosed coronary artery) and ruled-out with normal findings (both CTCA and MPS normal). Overall prevalence of significant CAD on QCA (>70% stenosis or 30-70% with FFR≤0.80) was 37%. Of 1004 pathological myocardial segments on MPS, 246 (25%) were reclassified from their standard coronary distribution to another territory by hybrid imaging. In this respect, in 45/252 (18%) patients, hybrid imaging reassigned an entire perfusion defect to another coronary territory, changing the final diagnosis in 42% of the cases. Hybrid imaging allowed non-invasive CAD rule-out in 41%, and rule-in in 24% of patients, with a negative and positive predictive value of 88% and 87%, respectively. CONCLUSION In patients at intermediate risk of CAD, hybrid imaging allows non-invasive co-localization of myocardial perfusion defects and subtending coronary arteries, impacting clinical decision-making in almost one every five subjects.

Cannabis: a trigger for acute myocardial infarction? A case report.

Cannabis smoking is consistently increasing in Europe and after alcohol it is the most common recreational drug in the western world. Users and lay people believe that marijuana or hashish is safe. Over the past four decades, however, it has been well established that cannabis has pathophysiological effects on the cardiovascular system. Information concerning the link between cannabis consumption and myocardial infarction is limited and existing data are controversial on this topic. In our case report, we describe a case of a young man who after smoking marijuana experienced ST elevation myocardial infarction caused by acute thrombosis of the descending artery, submitted to efficacious primary coronary angioplasty.

Cardiac amyloidosis: the heart of the matter

Amyloidosis comprises a unique group of diseases that share in common the extracellular deposition of insoluble fibrillar proteins in organs and tissue including the heart. Cardiac amyloidosis could be primary a part of systemic acquired amyloidosis, or a result of heredofamilial amyloidosis. Although the infiltration of the heart from different types of amyloid results in restrictive cardiomyopathy that manifests with refractory congestive heart failure and conduction abnormalities, unequivocal identification of the deposited amyloidogenic protein is mandatory in order to avoid misdiagnosis and inappropriate treatment. Recent developments in imaging techniques and extracardiac tissue biopsy have minimized the need for invasive endomyocardial biopsy for amyloidosis. Despite advances in treatment, the prognosis of a patient with amyloidosis is still poor and depends upon the underlying disease, and the type and degree of dysfunction of the involved organs. Thus, early diagnosis is mandatory because patients with advanced disease are usually too ill for intensive therapy. This review outlines current approaches to diagnosis, assessment of disease severity, and treatment of cardiac amyloidosis.

Adaptative or maladaptative hypertrophy, different spatial distribution of myocardial contraction.

Background:  Left ventricular hypertrophy (LVH) may be an adaptative remodelling process induced by physical training, or result from pathological stimuli. We hypothesized that different LVH aetiology could lead to dissimilar spatial distribution left ventricular (LV) contraction, and compared different components of LV contraction using 2‐dimensional (2‐D) speckle tracking derived strain in subjects with adaptative hypertrophy (endurance athletes), maladaptative hypertrophy (hypertensive patients) and healthy controls.