Diagnostic accuracy for detecting atrial fibrillation using a novel machine learning algorithm in a blood pressure monitor.

BACKGROUND: Early detection of atrial fibrillation (AF) is key for preventing strokes. Blood pressure monitors (BPMs) with built-in AF screening features have the potential for early detection at home. Recently, 2 BPMs (HEM-7371T1-AZ and HEM-7372T1-AZAZ, Omron Healthcare Co., Ltd.) that share a novel AF screening feature have been developed. Their AF screening feature utilizes an algorithm that incorporates machine learning, with the potential to improve diagnostic accuracy. OBJECTIVE: The purpose of this study was to evaluate the performance of this AF screening feature in a multicenter, prospective clinical study at 5 sites in the United States. METHODS: A total of 559 subjects were enrolled for this study: 267 in AF cohort and 292 in the non-AF cohort. AF screening was performed in all subjects by the 2 Omron BPMs and by 1 Microlife BPM (BP 3MX1-3, WatchBP Home A, Microlife Corp.), and a simultaneous 12-lead electrocardiogram (ECG) was recorded for comparison. All 12-lead ECGs were interpreted by a board-certified cardiologist who was blinded to the BPM results. Sensitivity, specificity, and accuracy for the diagnosis of AF were calculated. RESULTS: Omron HEM-7371T1-AZ BPM had sensitivity of 95.1% (95% confidence interval [CI] 91.8%-97.4%), specificity 98.6% (95% CI 96.6%-99.7%), and accuracy of 97.0% (95% CI 95.2%-98.2%). Equivalent results were obtained with the Omron HEM-7371T1-AZAZ BPM. This compared favorably to the Microlife BPM (sensitivity 78.5%, 95% CI 73.1%-83.3%; specificity 97.6%, 95% CI 95.1%-99.0%; accuracy 88.4%, 95% CI 85.5%-91.0%). CONCLUSION: These data support both home and professional use of these novel Omron BPMs for the detection of AF.

Utilizing three-dimensional echocardiography in cardioscopic left ventricular myxoma resection.

A 31-year-old female presented with right-sided stroke symptoms. She was found to have a left ventricular (LV) mass on transthoracic echocardiogram. Subsequent transesophageal echocardiogram (TEE) with concurrent three-dimensional (3D) imaging revealed a 2-cm mobile mass, suspicious for a myxoma, attached to the anteroseptal LV wall. Given the size and location of the mass seen on the 3D images, the cardiothoracic surgeons chose to avoid resection via aortotomy or ventriculotomy and instead performed video-assisted cardioscopic resection of the LV mass via left atriotomy. The mass was successfully removed, and pathology confirmed that it was a myxoma.

When an unidentified foreign object appears in the inferior vena cava: recognizing the presence of TIPS stent on transthoracic echocardiographic imaging.

We describe the case of 65-year-old female with a history of hypertension, diabetes, and cirrhosis. In the subcostal view on a routine transthoracic echocardiogram (TTE), she is found to have an unidentified round prosthetic appearing object in the inferior vena cava (IVC). Upon further investigation, the object was identified as a transjugular intrahepatic portosystemic shunt (TIPS) stent, which was seen in cross section in a hepatic vein draining into the IVC. Most echocardiographers are unfamiliar with the appearance of a TIPS on TTE. Being able to recognize this will help avoid misdiagnosis and unnecessary further imaging.

"Flap valve phenomenon" limiting aortic regurgitation in prosthetic valve dehiscence.

The authors describe the case of a 52-year-old man with a history of supra-annular mechanical aortic valve replacement who presented with fever and abdominal pain. He was found to have an abdominal wall abscess. Subsequent transesophageal echocardiography revealed dehiscence of his mechanical aortic valve, supporting a diagnosis of prosthetic valve endocarditis. Transesophageal echocardiography demonstrated that the dehisced aortic valve rocked on a hinge point, mimicking the motion of a flap valve. As the prosthetic valve rose with systole, it permitted flow into the aorta and, falling back in diastole, formed enough of a seal against the wall of the aortic annulus to limit aortic insufficiency. This "flap valve phenomenon" resulted in minimal perivalvular regurgitation, and the patient remained hemodynamically stable without heart failure before valve replacement.