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Purpose This study is to use a simple algorithm based on patient’s age to reduce the overall biological detriment associated with PET/CT. Materials and Methods A total of 421 consecutive patients (mean age 64 ± 14 years) undergoing PET for various clinical indications were enrolled. For each scan, effective dose (ED in mSv) and additional cancer risk (ACR) were computed both in a reference condition (REF) and after applying an original algorithm (ALGO). The ALGO modified the mean dose of FDG and the PET scan time parameters; indeed, a lower dose and a longer scan time were reported in the younger, while a higher dose and a shorter scan time in the older patients. Moreover, patients were classified by age bracket (18–29, 30–60, and 61–90 years). Results The ED was 4.57 ± 0.92 mSv in the REF condition. The ACR were 0.020 ± 0.016 and 0.0187 ± 0.013, respectively, in REF and ALGO. The ACR for the REF and ALGO conditions were significantly reduced in males and females, although it was more evident in the latter gender (all p < 0.0001). Finally, the ACR significantly reduced from the REF condition to ALGO in all three age brackets (all p < 0.0001). Conclusion Implementation of ALGO protocols in PET can reduce the overall ACR, mainly in young and female patients.

Introduction The aim of the narrative review was to analyse the applications of nuclear medicine (NM) techniques such as PET/CT with different tracers in combination with radiotherapy for the clinical management of glioblastoma patients. Materials and methods Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used. Results This paper contains a narrative report and a critical discussion of NM approaches in combination with radiotherapy in glioma patients. Conclusions NM can provide the Radiation Oncologist several aids that can be useful in the clinical management of glioblastoma patients. At the same, these results need to be validated in prospective and multicenter trials.

Purpose: Regorafenib (REG) has been recently approved for the treatment of relapsed glioblastoma. Contrast-enhanced (CE) magnetic resonance (MR) imaging represents the gold standard for diagnosis and surveillance of brain tumors. We evaluated the potential role of 18F-DOPA PET/CT in determining the response to REG in a case series of patients with recurrence of high-grade gliomas. Methods: Three patients with recurrence of high-grade gliomas underwent CE-MR and 18F-DOPA PET/CT within 1 week before and at 8-week intervals after REG therapy. 18F-DOPA PET was analyzed using qualitative and quantitative approaches. For the quantitative analysis, maximum (SUVmax), mean standardized uptake values (SUVmean) and metabolic tumor volume (MTV) were obtained. Results: In two patients, an early metabolic response to REG treatment, both visually and in terms of reduction of SUVmax, SUVmean and MTV, was observed. In one subject, no metabolic response was detected. Metabolic PET data were in agreement with morphological and perfusion MRI data in two patients. In one patient, while 18F-DOPA was able to correctly diagnose a metabolic response to REG, MRI had misdiagnosed a pseudo-progression of the disease. Discussion: These preliminary findings suggest that 18F-DOPA PET/CT allows an early and reliable assessment of metabolic response to the REG treatment. A major advantage of PET seems to be obtained in patients in whom MR is unable to differentiate non-response vs tumor pseudo-progression.

Purpose: The Italian Tailored Assessment of Lung Indeterminate Accidental Nodule (ITALIAN) trial is a trial drawn to determine the performance of 18F-FDG-PET/CT in patients with solitary pulmonary nodules (SPN), stratified for a different kind of risk. An additional end-point was to compare the diagnostic information and estimated dosimetry, provided by a segmental PET/CT (s-PET/CT) acquisition instead of a whole body PET/CT (wb-PET/CT), in order to evaluate if segmental thoracic PET/CT can be used in patients with SPN. Methods: 18F-FDG PET/CT of 502 patients, stratified for pre-test cancer risk, was retrospectively analyzed. FDG uptake in SPN was assessed by a 4-point scoring (4PS) system and a semiquantitative analysis using the ratio between SUVmax in SPN and SUVmean in mediastinal blood pool (BP), and between SUVmax in SPN and SUVmean in the liver (L). Histopathology and/or follow-up data were used as a standard of reference. Data obtained on the thoracic part of wb-PET/CT, defined as s - PET/CT, were compared with those deriving from wb-PET/CT. Results: SPNs were malignant in 180 patients (36%), benign in 175 (35%), and indeterminate in 147 (29%). The 355 patients diagnosed with a definitive SPN nature (malignant or benign) were considered for the analysis of PET performance. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy were 85.6%, 85.7%, 86%, 85.2%, and 85.6%, respectively. Sensitivity and PPV were higher in intermediate and high-risk patients. 18F-FDG uptake indicative of thoracic and extra-thoracic lesions was detectable in 13% and 3% of the patients. Compared to wb-PET/CT, s-PET/CT could save about 2/3 of 18F-FDG dose, radiation exposure or scan-time, without affecting the clinical impact of PET/CT. Conclusion: In patients with SPN, the pre-test likelihood of malignancy stratification allows to better define PET clinical setting and its diagnostic power. In subjects with low-intermediate pre-test likelihood of malignancy, s-PET/CT might be planned in advance. The adoption of this segmental strategy could reduce radiation exposure, scan-time, and might allow individually targeted protocols.

BACKGROUND Melanocytic lesions with eccentric hyperpigmentation (EH), even though without other dermatoscopic features of melanoma, are often excised. OBJECTIVE Aiming to understand whether the EH in a pigmented lesion is an accurate criterion of malignancy, we evaluated the capability of two evaluators, with different expertise, to correctly diagnose a melanoma when analysing a given lesion in toto versus a partial analysis, with only the EH or the non-hyperpigmented portion (non-EH) visible. METHODS Dermatoscopic images of 240 lesions (107 melanomas and 133 nevi) typified by EH were selected. Facial, acral, mucosal lesions and lesions showing clear-cut features of melanoma (except for atypical network) were excluded. Clinical and dermoscopic features (main pattern and numbers of colours) were described for all cases. Each image was split in two through a software so that only the EH or the non-EH was visible. Two blinded evaluators examined three sets of images, two with customized images and one with the non-modified ones: they were asked to give a dichotomous diagnosis (melanoma or nevus) for each image. RESULTS Melanomas were significantly more frequently typified by colour variegation (3 colours in 44.8% and 4 colours in 41.1% of cases) and atypical network (88.1% in the EH). No significant differences in diagnostic accuracy emerged between the two evaluators. Sensitivity improved in the evaluation of the whole lesions (mean sensitivity 89.7%) in comparison with the evaluation of EH or non-EH alone (72.7-62.6%). Specificity increased when evaluating the EH (54.1%). Positive predictive value (PPV) and likelihood ratio (LR+) of EH resulted 52.3% and 1.4, meaning that in one case out of two with EH is a melanoma. CONCLUSIONS Lesions with EH are challenging, regardless of dermoscopic experience. The EH is a robust criterion for malignancy, since the evaluation of the whole lesion, through an intralesional comparative approach, increases sensitivity.

BACKGROUND Neck aging is usually evaluated together with the lower face. To date, a skin laxity scale for the neck as an independent anatomical district is lacking. OBJECTIVE To create and validate a proposed photonumeric neck skin laxity (NSL) scale. MATERIALS AND METHODS Frontal neck photographic images of 110 subjects were collected. Each standardized neck image was evaluated twice by 3 independent doctors, 1 week apart. A 4-point photonumeric NSL scale was developed (0 = absence of skin laxity and 4 = severe skin laxity) and validated in terms of intraobserver and interobserver correlation and internal consistency. RESULTS The intraobserver reliability analysis of the 2 assessments performed by each observer revealed excellent correlation and consistency of the severity grading, independently of the time of evaluation (from 0.96 to 0.99, p < .01). Furthermore, the interobserver reliability analysis revealed an excellent agreement between the evaluators and an internal consistency independent of the evaluator (0.97, p < .01). CONCLUSION The newly developed NSL scale is a reliable and reproducible scoring system for the aesthetic evaluation of skin laxity of the neck.

Texture analysis (TA) can provide quantitative features from medical imaging that can be correlated to clinical endpoints. The challenges relevant to robustness of radiomics features have been analyzed by many researchers, as it seems to be influenced by acquisition and reconstruction protocols. Delta-texture analysis (D-TA), conversely, consist in the analysis of TA feature variations at different acquisition times, usually before and after a therapy. Aim of this study was to investigate the influence of different CT scanners and acquisition parameters in the robustness of TA and D-TA. We scanned a commercial phantom (CIRS model 467, Gammex, Middleton, WI, USA), that is used for the calibration of electron density, two times by varying the disposition of plugs, using three different scanners. After the segmentation, we extracted TA features with LifeX and calculated TA features and D-TA features, defined as the variation of each TA parameters extracted from the same position by varying the plugs with the formula (Y–X)/X. The robustness of TA and D-TA features were then tested with intraclass coefficient correlation (ICC) analysis. The reliability of TA parameters across different scans, with different acquisition parameters and ROI positions has shown poor reliability in 12/37 and moderate reliability in the remaining 25/37, with no parameters showing good reliability. The reliability of D-TA, conversely, showed poor reliability in 10/37 parameters, moderate reliability in 10/37 parameters, and good reliability in 17/37 parameters. The comparison between TA and D-TA ICCs showed a significant difference for the whole group of parameters (p:0.004) and for the subclasses of GLCM parameters (p:0.033), whereas for the other subclasses of matrices (GLRLM, NGLDM, GLZLM, Histogram), the difference was not significant. D-TA features seem to be more robust than TA features. These findings reinforce the potentiality for using D-TA features for early assessment of treatment response and for developing tailored therapies. More work is needed in a clinical setting to confirm the results of the present study.

Objective Patients with solitary pulmonary nodule (SPN) are usually sent to total-body positron emission tomography/computed tomography (PET/CT) examination with 18F-fluorodeoxyglucose (FDG). However, a segmental scan strategy may improve cost/effectiveness in this category of patients. Conclusion A segmental PET/CT scan only at the chest level could be performed in patients with indeterminate SPN. Limiting the PET/CT field to the thoracic region would greatly affect on radiobiology, department organization and health-care costs.

Diagnosis of solitary pulmonary nodule (SPN) is an important public health issue andIn the study population, 36% had malignant, 35% benign, and 29% indeterminate SPN.Pre-test probability of malignancy can guide the diagnostic strategy of

Purpose: The aim of this study was to determine the performance of 18F-FDG-PET/CT in patients with solitary pulmonary nodule (SPN), stratifying the risk according to the likelihood of pulmonary malignancy. Methods: FDG-PET/CT of 502 patients, stratified for pre-test cancer risk, were retrospectively analyzed. FDG uptake in SPN was assessed by a 4-point scoring system and semiquantitative analysis using the ratio between SUVmax in SPN and SUVmean in mediastinal blood pool (BP) and between SUVmax in SPN and SUVmean in liver (L). Histopathology and/or follow-up data were used as standard of reference. Results: SPN was malignant in 180 (36%) patients, benign in 175 (35%), and indeterminate in 147 (29%). The 355 patients with a definitive SPN nature (malignant or benign) were considered for the analysis. Considering FDG uptake ≥2, sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, and accuracy were 85.6%, 85.7%, 86%, 85.2%, and 85.6% respectively. Sensitivity and PPV were higher (P&nbsp

PURPOSE: Diagnosis of solitary pulmonary nodule (SPN) is an important public health issue and 18F-FDG PET/CT has proven to be more effective than CT alone. Pre-test risk stratification and clinical presentation of SPN could affect the diagnostic strategy. A relevant issue is whether thoracic segmental (s)-PET/CT could be implemented in patients with SPN. This retrospective multicenter study compared the results of FDG whole-body (wb)-PET/CT to those of s-PET/CT. METHODS: 18F-FDG PET/CT of 502 patients, stratified for pre-test cancer risk, were retrospectively analyzed. The thoracic part of wb-PET/CT, considered s-PET/CT, was compared to wb-PET/CT. Clinical and PET/CT variables were investigated for SPN characterization as well as for identification of patients in whom s-PET/CT could be performed. Histopathology or follow-up data were used as a reference. RESULTS: In the study population, 36% had malignant, 35% benign, and 29% indeterminate SPN. 18F-FDG uptake indicative of thoracic and extra-thoracic lesions was detectable in 13% and 3% of the patients. All patients with extra-thoracic metastases (n = 13) had thoracic lymph node involvement and highest 18F-FDG uptake at level of SPN (negative predictive value 100%). Compared to wb-PET/CT, s-PET/CT could save about 2/3 of 18F-FDG dose, radiation exposure or scan-time, without affecting the clinical impact of PET/CT. CONCLUSION: Pre-test probability of malignancy can guide the diagnostic strategy of 18FDG-PET/CT in patients with SPN. In subjects with low-intermediate pretest probability s-PET/CT imaging might be planned in advance, while in those at high risk and with thoracic lymph node involvement a wb-PET/CT is necessary.

Background The Italian Tailored Assessment of Lung Indeterminate Accidental Nodule (ITALIAN) is a retrospective, multicenter trial designed to compare the diagnostic information provided by segmental positron emission tomography (PET)/computed tomography (CT) (s-PET/CT) with those of whole body (wb)-PET/CT in patients with single pulmonary nodules (SPN). This report describes the details and implications of the ITALIAN trial design. Methods and results Between September 2016 and May 2017, 502 consecutive patients (302 men, mean age 67±12 years) with SPN undergoing 18F-fluorodeoxyglucose (FDG) PET/CT were enrolled. PET/CT images will be visually and semiquantitatively evaluated. For visual analysis, a 4-point scoring system (1=absent; 2=mild; 3=moderate and 4=intense) will be used; for semiquantitative analysis, maximum standardized uptake value (SUV) in the SPN and mean SUV in the mediastinal blood pool and in the liver will be computed. Conclusion The results of this trial might help to define the role of s-PET/CT in patients with SPN. This trial will also evaluate the impact on radiobiology and costs subsequent the introduction of this alternative imaging acquisition modality.

Patients with solitary pulmonary nodule (SPN) are usually sent to total-body positron emission tomography/computed tomography (PET/CT) examination with 18F-fluorodeoxyglucose (FDG). However, a segmental scan strategy may improve cost/effectiveness in this category of patients.A segmental PET/CT scan only at the chest level could be performed in patients with indeterminate SPN. Limiting the PET/CT field to the thoracic region would greatly affect on radiobiology, department organization and health-care costs.

To design proactive and autonomous interactive objects, designers deal with the design of the object's behavior. In this paper, we propose a design method, called Personality, to help designers develop interactive objects' behaviors with a focus on aesthetics of interaction; the method focuses on tangible and bodily interaction, and it includes four main steps. The "unguided improvisation" step consists of an initial interplay with the interactive object in order to size up the interaction; a brainstorming step, in which we use stereotypes of personalities to create metaphors, to support the discussion around, and the description of, possible behaviors; the "guided improvisation" step iterates over several improvisation sessions to act out interaction scenarios and behaviors; and the behavior synthesis step, in which we provide a final description of the object's behavior. To illustrate Personality we will describe the sofa-bot case study. We will report a lab study, in which we observed people reaction to the different behaviors of the sofa.

The aim of the study was to evaluate a novel polar map of myocardial viability obtained by gated SPECT imaging to predict functional recovery after revascularization in patients with ischaemic left ventricular (LV) dysfunction. The study group comprised 17 patients (15 men, mean age 58 +/- 9 years) with ischaemic LV dysfunction (ejection fraction

Thermostats allow people to set the temperature they desire, even if personal thermal comfort perception is tied to a number of external stimuli [9]. Here we investigate dependability of people's thermal comfort, from the multi-sensory features of environment (light colors). We want to prototype a system that influences people's thermal comfort through other stimuli instead of temperature changing. The preliminary Spell research envisions a smart system for heating control that proactively compensates temperature variations using light color variations, accomplishing both the objectives: to satisfy user request for thermal comfort, while optimizing energy consumption. Two preliminary experiments were made: one demonstrates that people's perceived temperature is different from the actual temperature in a space; the second one shows how lights color affects the temperature perceived by people. As a result we derived preliminary guidelines for the prototyping the Spell system.

A combined surgical procedure, left ventricular restoration (LVR), consisting of coronary artery bypass graft and endoventricular patch plasty (EPP), is under investigation in on-going STICH trial (1). EPP may provide restoration of left ventricular (LV) size and geometry by excluding nonviable areas. At present, the differentiation of viable tissue and scar is based on subjective methods, assessing morphological features such as consistency, thickness and color of the wall, and it may be inadequate on surgery table. We assessed the feasibility of in vivo radioguided surgery (RGS) by a gamma-probe as an objective tool to differentiate viable tissue and scar in patients undergoing EPP.

To determine whether stress–rest myocardial perfusion single-photon emission (MPS) computed tomography improves coronary heart disease (CHD) risk classification in diabetic patients. In 822 consecutive diabetic patients, risk estimates for a CHD event were categorized as 0% to

To evaluate the effects of the addition of atropine to exercise testing in patients who failed to achieve their target heart rate (HR) during stress myocardial perfusion imaging with single-photon emission computed tomography (SPECT). The study was a prospective, randomized, placebo-controlled design. Patients with suspected or known coronary artery disease who failed to achieve a target HR (≥85% of maximal predicted HR) during exercise SPECT imaging were randomized to receive intravenous atropine (n = 100) or placebo (n = 101). The two groups of patients did not differ with respect to demographic or clinical characteristics. A higher proportion of patients in the atropine group achieved the target HR compared to the placebo group (60% versus 3%, p

BACKGROUND To evaluate the relevance of diastolic perfusion time on the mechanisms underlying stress-induced ischemia, 16 patients with coronary artery disease and seven patients with syndrome X underwent five randomized stress tests (upright and supine exercise with and without therapy, transesophageal atrial pacing). METHODS AND RESULTS Exercise duration Time to 0.1 mV ST segment depression, heart rate, rate-pressure product, and diastolic perfusion time were evaluated for each patient during stress tests. In both groups, variability coefficients of the above-mentioned parameters were not different at rest. At ischemic threshold (0.1 mV ST segment depression) in patients with coronary artery disease, the variability coefficient of exercise duration (40.1 +/- 22.2) was significantly higher (p less than 0.0001) than those of heart rate (12.8 +/- 2.9), rate-pressure product (14.8 +/- 3.3), and diastolic perfusion time (0.39 +/- 0.1). The variability coefficient of diastolic perfusion time was also significantly (p less than 0.0001) lower than those of heart rate and rate-pressure product. Similarly, the variability coefficient of diastolic perfusion time (0.44 +/- 0.1) in syndrome X patients was significantly lower (p less than 0.0001) than those of exercise duration (28.2 +/- 9.4), heart rate (12 +/- 1.4), and rate-pressure product (14.6 +/- 1.3). CONCLUSIONS Fixed diastolic perfusion time at ischemic threshold, despite different kinds of stress tests and variability of heart rate and rate-pressure product, indicates the relevant role of diastolic perfusion time in determining myocardial ischemia.

The ratio between the integrated pressure difference between aorta and left ventricle during diastole (diastolic pressure-time index; DPTI) and the area beneath the systolic portion of the left ventricular pressure curve (systolic pressure-time index; SPTI) is an invasive estimate of myocardial oxygen supply and demand. In order to provide a noninvasive method to assess myocardial oxygen supply/demand, 42 patients (group I) without transaortic valvular pressure gradient and 10 patients (group II) with 57.6±26.4 mm Hg pressure gradient were evaluated

Since an abnormal shortening of diastolic duration during exercise in the patients with coronary artery disease was demonstrated, time course of diastolic period (cardiac cycle minus electromechanical systole) calculated from polycardiographic recording has been assessed in patients with X syndrome and in normal age-matched subjects during supine ergometer exercise. All patients with X syndrome had positive exercise stress response (more than 0.1 mV of ST segment depression). Duration of diastole expressed as percent of cardiac cycle was significantly shorter at the intermediate steps and at the peak of exercise in patients with X syndrome compared with normal subjects (p less than 0.05). When the relationship between heart rate and diastolic time was examined, an inverse nonlinear regression was found both in normal subjects and in patients with X syndrome. The exercise values of diastolic time observed in patients with X syndrome were significantly shorter than those predicted as normal diastolic time heart rate relation. Thus the patients with X syndrome demonstrated abnormalities in the decrement of diastolic time with exercise. We hypothesized that this disproportionate shortening, by reducing subendocardial blood flow, might induce a worsening of ischemic response to exercise.

Cardiovascular disease is a major cause of morbidity and mortality in chronic kidney disease. Radionuclide-based methods can be used for analyses on the perfusion of coronary arteries and ventricular function. The present study reports the use of a new procedure for continuous measurements of left ventricle function during a dialytic session with the use of a recently developed portable gamma radiation detector (ventricular function study system). On average, left ventricle ejection fraction and stroke volume progressively and continuously decreased throughout the session (end session versus baseline: -13.8% for ejection fraction, -25.9% for stroke volume, P < .02). A biphasic response was found for heart rate: a transient modest decrease (at session midpoint, -4.2%) followed by an increase up to values higher than baseline (end session, +4.7%). Cardiac output decreased by 10.4% at session midpoint (P = .023 versus baseline) without further reduction in the following hours. Mean changes in systolic pressure paralleled data for cardiac output. Individual changes in indices of left ventricle function were scattered and strongly were correlated with thickness of interventricular septum and telediastolic left ventricular volume measured by standard echocardiogram in the interdialytic period (R > .75, P < .05). Data indicate that the ventricular function study system could be a powerful tool for characterization of the profile of left ventricular function in hemodialyzed patients. © 2006 Elsevier Inc. All rights reserved.

Myocardial uptake of 99Tcm-tetrofosmin in vivo is determined by a combination of flow and metabolic status of myocytes. The accumulation of tetrofosmin in the mitochondria is related to their ability to transduce metabolic energy into electronegative membrane potential. Trimetazidine (TMZ), an anti-ischaemic drug, appears to have a metabolic cytoprotective effect related to mitochondrial function, since it does not induce systemic or coronary haemodynamic changes. In this study, we evaluated the effects of TMZ on tetrofosmin uptake in hypoperfused myocardial regions in patients with coronary artery disease (CAD). Twenty-two patients, 14 with previous myocardial infarction (group A) and eight with a history of angina (group B), with angiographically documented CAD were studied. All patients underwent two tetrofosmin SPET studies at rest, before (baseline) and 1 week after TMZ administration (post-TMZ). On quantitative analysis, 131 segments showed less tetrofosmin uptake at baseline. In these segments, tetrofosmin uptake was 51 +/- 13% at baseline and 55 +/- 15% post-TMZ (P < 0.001 vs control). In the 86 hypoperfused segments of group A, tetrofosmin uptake was 48 +/- 14% at baseline and 52 +/- 17% post-TMZ (P < 0.001 vs control). In the 45 hypoperfused segments of group B, tetrofosmin uptake was 56 +/- 9% at baseline and 60 +/- 10% post-TMZ (P < 0.001 vs control). In the remaining 309 segments, no significant difference in tetrofosmin uptake before and after TMZ was observed. In conclusion, our results suggest that TMZ administration may increase myocardial uptake of tetrofosmin in hypoperfused regions at rest in patients with CAD, based on its metabolic effect.

It is well known that cardiovascular response to exercise involves sympathetic stimulation of the heart and peripheral vessels and that β blockade interferes with adrenergic response during exercise. When a decrease in heart rate is prevented by atrial pacing, regional myocardial function and blood flow in ischemic areas tend to be more depressed after β blockade, suggesting that β blockade could unmask an α 2 adrenergic vasoconstriction, worsening regional blood flow and function. 1 An alternative hypothesis might be that β blockade modifies the relation between diastolic time and heart rate. In fact, there is also some evidence that β blockade impairs the postexercise diastolic time in patients with coronary artery disease. 2 However, this effect is not clearly explained, since ischemia alone could interfere with diastole duration. 3,4 Moreover, the effect of β blockade on diastolic time during exercise is still unknown. This study investigates the effects of β blockade on diastolic time during exercise in hypertensive patients without stress-induced myocardial ischemia.

The present study has been performed to assess the effects of alinidine on diastolic duration during exercise in chronic coronary artery disease. Twelve male patients with stable effort angina and without previous myocardial infarction were studied. They received alinidine or placebo in a double-blind randomized crossover trial for 3 days after a wash-out period of 4 days. Alinidine was administered at a dosage of 30 mg 3 times a day. At the end of each treatment the patients underwent upright bicycle exercise. Left ventricular time intervals were obtained by means of carotid thermistor plethysmography. Diastolic duration was calculated by subtracting the electromechanical systole from the R-R interval and expressed as a percentage of the cardiac cycle (%D). Alinidine increased both total exercise duration from 246.7 +/- 120.7 to 346.6 +/- 114.1 s (p less than 0.05) and time to 0.1-mV ST segment depression from 98.3 +/- 53 to 187.2 +/- 105 s (p less than 0.05). Similarly the drug induced a reduction of the rate-pressure product and of the extent of ischemic ST segment depression during exercise. %D was increased by alinidine both at rest and during exercise. A direct linear regression between R-R and %D was found after both alinidine and placebo treatments either at rest or during exercise. Nevertheless, no difference was observed between both slopes and intercepts. Therefore, since the relationship between R-R interval and %D was unaffected by alinidine, it was possible to hypothesize that the changes in diastolic duration were due only to the bradycardic action of the drug.