Handheld ultrasound in cardiology: Current perspective.

The advantages of ultrasonography do not need to be discussed. It is suitable for use in diverse clinical settings and environments by operators with different backgrounds. Recent technological advances have led not only to the enhancement of the diagnostic capabilities of stationary ultrasound systems but also to miniaturization, which in turn led to the introduction of smartphone-sized handheld ultrasound devices (HUDs), designed to be used at bedside to improve and extend the scope of physical examination. Although diagnostic capabilities of HUDs are expanding, according to guidelines, they cannot be perceived as a tool suitable for performing full echocardiographic examination. However, their ultraportability made them essential for the bedside assessment, with the particular emphasis on the bedside focus cardiac ultrasound (FoCUS)-goal-oriented, limited echocardiographic screening. Clinically relevant cardiological targets suggested for HUDs include the assessment of left ventricular (LV) systolic function and size, assessment of other cardiac chambers, identification of gross valvular abnormalities, and detection of the pathological masses within the heart cavities. Handheld ultrasound devices may be also helpful in identifying pleural effusion or subpleural consolidations; furthermore, brief ultrasonographic assessment of "lung comets" enables the estimation of the level of congestion. Ultrasound screening for certain vascular abnormalities also appears promising. The limitations of HUDs are rather obvious and caution is needed to distinguish the role of HUD-based bedside-limited scan from comprehensive stationary echocardiography. It appears that the right approach is to treat them as complementary tools proving their capabilities in diverse clinical scenarios.

Integrated Assessment of Heart, Lung and Lower Extremity Veins Using Hand-Held Ultrasound Device in COVID-19 Patients: Feasibility and Clinical Application.

The emergence of the COVID-19 pandemic caused a significant shortage of medical personnel and the prioritization of life-saving procedures on internal medicine and cardiology wards. Thus, the cost- and time-effectiveness of each procedure proved vital. Implementing elements of imaging diagnostics into the physical examination of COVID-19 patients could prove beneficial to the treatment process, providing important clinical data at the moment of admission. Sixty-three patients with positive COVID-19 test results were enrolled into our study and underwent physical examination expanded with a handheld ultrasound device (HUD)-performed bedside assessment included: right ventricle measurement, visual and automated LVEF assessment, four-point compression ultrasound test (CUS) of lower extremities and lung ultrasound. Routine testing consisting of computed-tomography chest scanning, CT-pulmonary angiogram and full echocardiography performed on a high-end stationary device was completed in the following 24 h. Lung abnormalities characteristic for COVID-19 were detected in CT in 53 (84%) patients. The sensitivity and specificity of bedside HUD examination for detecting lung pathologies was 0.92 and 0.90, respectively. Increased number of B-lines had a sensitivity of 0.81, specificity 0.83 for the ground glass symptom in CT examination (AUC 0.82; p < 0.0001); pleural thickening sensitivity 0.95, specificity 0.88 (AUC 0.91, p < 0.0001); lung consolidations sensitivity 0.71, specificity 0.86 (AUC 0.79, p < 0.0001). In 20 patients (32%), pulmonary embolism was confirmed. RV was dilated in HUD examination in 27 patients (43%), CUS was positive in two patients. During HUD examination, software-derived LV function analysis failed to measure LVEF in 29 (46%) cases. HUD proved its potential as the first-line modality for the collection of heart-lung-vein imaging information among patients with severe COVID-19. HUD-derived diagnosis was especially effective for the initial assessment of lung involvement. Expectedly, in this group of patients with high prevalence of severe pneumonia, HUD-diagnosed RV enlargement had moderate predictive value and the option to simultaneously detect lower limb venous thrombosis was clinically attractive. Although most of the LV images were suitable for the visual assessment of LVEF, an AI-enhanced software algorithm failed in almost 50% of the study population.

Artificial Intelligence-Powered Measurement of Left Ventricular Ejection Fraction Using a Handheld Ultrasound Device.

The aim of this study was to assess the accuracy of an algorithm for automated measurement of left ventricular ejection fraction (LVEF) available on handheld ultrasound devices (HUDs). One hundred twelve patients admitted to the cardiology department underwent assessment performed with an HUD. In each case, the four-chamber apical view was obtained, and LVEF was calculated with LVivo software. Subsequently, during the examination performed with the use of the stationary echocardiograph, the 3-D measurement of LVEF was recorded. The average LVEFs measured with LVivo and the 3-D reference method were 46 ± 14% and 48 ± 14%, respectively. The correlation between the measurements obtained with the HUD and 3-D evaluation was high (r = 0.92, 95% confidence interval: 0.87-0.95, p < 0.0001). The mean difference between the LVEF obtained with LVivo and the 3-D LVEF was not significant (mean difference: -0.61%, 95% confidence interval: -1.89 to 0.68, p = 0.31). The LVivo software despite its limitations is capable of the accurate LVEF measurement when the acquired views are of at least good imaging quality.

Personal mobile device-based pocket echocardiograph-The diagnostic value and clinical utility.

PURPOSE: A microUSB ultrasound probe, which can be connected to a personal mobile device constitutes a new class of diagnostic pocket-size imaging devices (PSID). The aim of this study was to assess the feasibility and diagnostic value of brief transthoracic echocardiographic examination (bTTE) performed with the use of such equipment. MATERIAL AND METHODS: The study population comprised 87 consecutive patients (58 men, mean age 61 ± 16 years), 53 of whom were admitted to intensive cardiac care unit and 34 patients, who were referred for transthoracic echocardiography from outpatient clinic. All patients underwent bTTE performed by cardiologist with the use of personal mobile device-based PSID. Within 18 h of bTTE all subjects underwent a standard TTE (sTTE) using a full sized echocardiograph by expert echocardiographer. RESULTS: In all patients, PSID imaging provided sufficient diagnostic image quality. Echocardiographic measurements were completed for both bTTE and sTTE in 98% of patients. The linear measurements obtained during bTTE showed good to excellent correlation with sTTE results (r = 0.65-0.98; p < 0.001). The agreement in detection of various pathologies between the bTTE and sTTE examination was very good (k = 0.62-0.97; p < 0.01). CONCLUSION: Personal mobile device-based PSID allows for performing bTTE. The diagnostic value of such PSID in basic assessment of cardiac morphology and function as compared to standard echocardiography is very good.

Brief cardiovascular imaging with pocket-size ultrasound devices improves the accuracy of the initial assessment of suspected pulmonary embolism.

Pulmonary embolism onset is frequently neglected due to the non-specific character of its symptoms. Pocket-size imaging devices (PSID) present an opportunity to implement imaging diagnostics into conventional physical examination. The aim of this study was to test the hypothesis that supplementation of the initial bedside assessment of patients with suspected pulmonary embolism (PE) with four-point compression venous ultrasonography (CUS) and right ventricular size assessment with the use of PSID equipped with dual probe could positively influence the accuracy of clinical predictions. A single-centre, prospective analysis was conducted on 100 patients (47 men, mean age 68 ± 13 years) with suspected PE. Clinical assessment on the basis of Wells and revised Geneva score and physical examination were supplemented with CUS and RV measurements by PSID. The mean time of PSID scanning was 4.9 ± 0.8 min and was universally accepted by the patients. Fifteen patients had deep venous thrombosis and RV enlargement was observed in 59 patients. PE was confirmed in 24 patients. If the both CUS was positive and RV enlarged, the specificity was 100% and sensitivity 54%, ROC AUC 0.771 [95% CI 0.68-0.85]. The Wells rule within our study population had the specificity of 86% and sensitivity of 67%, ROC AUC 0.776 (95% CI 0.681-0.853, p < 0.0001). Similar values calculated for the revised Geneva score were as follows: specificity 58% and sensitivity 63%, ROC AUC 0.664 (95% CI 0.563-0.756, p = 0.0104). Supplementing the revised Geneva score with additional criteria of CUS result and RV measurement resulted in significant improvement of diagnostic accuracy. The difference between ROC AUCs was 0.199 (95% Cl 0.0893-0.308, p = 0.0004). Similar modification of Wells score increased ROC AUC by 0.133 (95% CI 0.0443-0.223, p = 0.0034). Despite the well-acknowledged role of the PE clinical risk assessment scores the diagnostic process may benefit from the addition of basic bedside ultrasonographic techniques.

Bedside screening with the use of pocket-size imaging device can be useful for ruling out carotid artery stenosis in patients scheduled for cardiac surgery.

BACKGROUND: Patients (pts) scheduled for coronary artery bypass grafting, burdened with high risk of carotid stenosis, are recommended to undergo duplex ultrasonography (DUS) of carotid arteries. PURPOSE: To validate pocket-size imaging device (PSID) equipped with linear probe as an easily accessible tool enabling bedside screening for carotid artery stenosis (CAS). METHODS: A total of 100 pts (60 men, mean age 69±11 years) with multivessel coronary artery disease underwent bedside DUS of carotid arteries with the use of PSID performed by a cardiology resident trained in DUS. Subsequently, DUS with the use of stationary high-end ultrasound system was performed in all pts to verify findings of PSID examination. RESULTS: Initial diagnosis of atherosclerotic plaque presence obtained with PSID in 59 patients was confirmed by high-end ultrasound system examination in all cases. There was a statistically significant correlation of intima-media thickness measurements between PSID and stationary system (r=.58; 95% CI: 0.48-0.66; P<.0001), but the coefficient of agreement (κ) between the two methods in classification of intima-media as normal or thickened (>0.9 mm) was only .38 (95% CI: 0.299-0.459). During PSID examination, turbulent flow was observed in 21 pts-CAS was confirmed in all these pts-5 pts were diagnosed with significant CAS, the rest with CAS ranging from 30% to 70%. CONCLUSIONS: Pocket-size imaging device equipped with linear probe allows for identification of patients with atherosclerotic plaques and turbulent flow in carotid arteries; however, the degree of CAS cannot be reliably determined. The measurement accuracy of intima-media thickness is insufficient for a diagnostic purpose.

The influence of lidocaine topical anesthesia during transesophageal echocardiography on blood methemoglobin level and risk of methemoglobinemia.

Methemoglobinemia is a relatively rare, but potentially life-threating medical condition, which may be induced by application of topical anaesthetic agents commonly used during endoscopic procedure. The aim of our study was to assess the influence of lidocaine used prior to transesophageal echocardiography (TEE) on the blood level of methemoglobin in vivo. Additionally we attempted to establish the occurrence rate of clinically evident lidocaine-induced methemoglobinemia on the basis of data collected in our institution. We retrospectively analyzed patient records from 3,354 TEEs performed in our echocardiographic laboratory over the course of 13 years in search for clinically evident methemoglobinemia cases. Additionally, 18 consecutive patients referred for TEE were included in the prospective part of our analysis. Blood samples were tested before and 60 min after pre-TEE lidocaine anesthesia application. Information concerning concomitant conditions and pharmacotherapy were also obtained. In 3,354 patients who underwent TEE in our institution no cases of clinically evident methemoglobinemia occurred. In the prospective part of the study, none of 18 patients [16 (89 %) men, mean age 63 ± 13] was diagnosed with either clinical symptoms of methemoglobinemia or exceeded normal blood concentration of methemoglobin. Initial mean methemoglobin level was 0.5 ± 0.1 % with mild, statistically (but not clinically) significant rise to 0.6 ± 0.1 % after 60 min (p = 0.02). Among the analyzed factors only the relation between the proton pump inhibitors intake and methemoglobin blood level rise was identified as statistically relevant (p = 0.03). In adults, pre-TEE lidocaine anesthesia with recommended dosage results in significant increase in methemoglobin blood level, which however does not exceed normal values and does not result in clinically evident methemoglobinemia.

Prognostic Implications of Discordant Results of Myocardial Perfusion Single-Photon Emission Computed Tomography and Exercise ECG Test in Patients with Stable Angina.

BACKGROUND: ECG exercise treadmill test (ExT) and myocardial perfusion SPECT (single photon emission computed tomography) study are widely used for the non-invasive evaluation of patients with coronary artery disease (CAD). OBJECTIVES: To assess long-term prognosis in patients with suspected or known coronary artery disease (CAD), in whom ECG exercise treadmill test (ExT) and myocardial perfusion single photon emission computed tomography (SPECT) provided discordant results are lacking. MATERIAL AND METHODS: Four hundred eighty three patients with suspected or known stable CAD underwent 99mTc-methoxyisobutylisonitrile SPECT and ExT. SPECT was considered positive (+) if inducible or mixed perfusion defects were detected. ExT was evaluated using widely accepted criteria. Based on the results of both examinations the patients were divided into 4 subgroups: group 1 - SPECT (+) and ExT (+), group 2 - SPECT (+) and ExT (-), group 3 - SPECT (-) and ExT (+), group 4 - SPECT (-) and ExT (-). RESULTS: After a mean follow-up of 59 ± 7 months, major cardiac events (cardiac death and nonfatal myocardial infarction combined) and revascularizations were more prevalent in groups 1 and 2 than in groups 3 and 4. However, the statistical significance (p ≤ 0.01) was reached only for the following differences: in major cardiac events - group 1 vs group 3 and group 1 vs group 4; in revascularizations - group 1 vs. group 3, group 1 vs. group 4 and group 2 vs group 4 and in cardiac hospitalizations - group 1 vs. group 4 and group 2 vs. group 4. CONCLUSIONS: Positive myocardial perfusion SPECT result is associated with similar clinical outcome irrespectively of ExT result in long-term follow-up.

Pocket-size imaging devices allow for reliable bedside screening for femoral artery access site complications.

The aim of this study was to validate pocket-size imaging devices (PSIDs) as a fast screening tool for detecting complications after femoral artery puncture. Forty patients undergoing femoral artery puncture for arterial access related to percutaneous coronary intervention were enrolled. Twenty-four hours after percutaneous coronary intervention, the involved inguinal region was assessed with PSIDs enabling 2-D gray-scale and color Doppler imaging. Subsequently, examination with a stationary high-end ultrasound system was performed to verify the findings of bedside examination in all patients. In 37 patients, PSID imaging had good diagnostic quality. False aneurysms (one asymptomatic) occurred in four patients, and all were recognized during bedside screening with PSID. One case of femoral artery thrombosis was confirmed with PSID and during standard ultrasonographic examination. Physical examination augmented with the quick bedside PSID examination had a sensitivity of 100% and specificity of 91%. PSID facilitated rapid bedside detection of serious access site complications in the vast majority of patients, including asymptomatic cases.

Long-term prognostic value of inducible and resting perfusion defects detected by single-photon emission computed tomography in the era of wide availability of coronary revascularization.

PURPOSE: To assess the long-term prognostic value of various types of perfusion defects detected by single-photon emission computed tomography (SPECT) in patients with stable angina. METHODS: Seven hundred and thirty two patients (299 men, mean age 57 ± 9 years) with suspected or known stable coronary artery disease underwent rest/exercise SPECT protocol using 99mTc-methoxyisobutylisonitrile (MIBI). All patients completed clinical follow-up regarding cardiac events (cardiac death, sudden cardiac death, acute coronary syndrome, revascularization, cardiac hospitalization) for a mean period of 58 ± 8 months. Event rates were analysed in subgroups defined according to the presence of fixed or inducible myocardial perfusion defects. RESULTS: During the follow-up, 15 cardiac deaths were recorded, 13 of which were qualified as a sudden cardiac death, 59 acute coronary syndromes, 65 revascularizations and 209 cardiac hospitalizations. The presence of inducible perfusion defects on SPECT was associated with a high risk for occurrence of all analysed end points: sudden cardiac death (HR = 3·96, P = 0·01), cardiac hospitalization (HR = 1·5, P = 0·004), coronary syndrome (HR = 2·33, P = 0·001) and coronary revascularization (HR = 2·76, P = 0·0002), except for the cardiac death (P = 0·27). Resting perfusion defects were highly predictive for cardiac death (HR = 7·45; P = 0·001), but not for other cardiac events (P = NS). The presence of any (inducible or resting) perfusion defects was associated with a high risk of all cardiovascular complications. CONCLUSIONS: In long-term follow-up, SPECT proved highly predictive of cardiac events in patients with suspected or known CAD. In the revascularization era, cardiac death is most accurately related to the presence of resting perfusion defects, but all other cardiac events were better predicted by inducible perfusion defects.