Right ventricular thrombus, a challenge in imaging diagnostics: a case series.

BACKGROUND: Presence of right ventricular thrombus (RVT) is a rare but life-threatening condition, thus immediate diagnosis and therapy are mandatory. Unfortunately, detection and distinction from intraventricular tumour masses or vegetations represent a complex task. Furthermore, consecutive therapy is principally led by clinical presentation without considering morphological features of the thrombus. Current literature suggests a multimodal non-invasive imaging approach. In this article, we discuss the role of cardiac magnetic resonance imaging (CMR) for the detection of RVT in patients with pulmonary embolism (PE). We consider the relatively expensive and not broadly available imaging procedure and weigh it up to its assumed high sensitivity, specificity, and importance for differential diagnosis and therapeutic decision-making. CASE SUMMARY: In this case series, we report three cases of RVT with concomitant PE, whereof two were missed during routine cardiac workup by transthoracic echocardiography and computer tomography. Cardiac magnetic resonance imaging led to detection and further characterization of the thrombi in both cases. CONCLUSIONS: Cardiac magnetic resonance imaging reliably detects and characterizes RVT, even under unfavourable conditions for echocardiography such as arrhythmia, adiposity, or in posterior position of RVT. Obtained information could facilitate the choice of therapeutic approach (anticoagulation vs. systemic lysis vs. surgical thrombectomy). Future risk stratification scores will promote cost-effective use of CMR.

A significant increase in exercise test performance with virtual group motivation: a randomised open-label controlled trial.

AIMS: Exercise stress testing is frequently used for the assessment of coronary artery disease. As the validity of the test result is highly dependent on the patient’s cooperation and motivation, we hypothesised that virtual group motivation would result in a higher exercise capacity and may increase the test’s validity. METHODS: 108 patients at a Swiss teaching hospital with an indication for exercise testing were included in a controlled, open-label trial and randomised 1:1 to treadmill exercise testing whilst either watching a video of a walking group (video group, n = 43), or watching a static image of flowers (image group, n = 43). The video showed a group of five amateur runners, giving the patients the impression of running within the group. As primary outcomes, the performance achieved and the perceived level of comfort during the test were analysed. RESULTS: The video group achieved significantly higher percentages of their age-predicted METs (149 ± 32% vs 135 ± 29%, p = 0.041) and longer exercise durations (11:12 ± 2:54 min vs 08:54 ± 02:39 min, p <0.001). Levels of comfort (8.4 ± 1.4 vs 7.5 ± 1.7 analogue scale, p = 0.011) and closeness to their physical limits (8.9 ± 0.8 vs 8.1 ± 1.5, p = 0.005) were rated significantly higher by patients in the video group. CONCLUSIONS: Patients watching a video of a running group achieved significantly higher maximum exercise levels and longer test durations. This may have implications for the test’s validity. Furthermore, the virtual setting enhanced patient comfort. (This trial was formally registered at clinicaltrials.gov: trial ID NCT03704493.).

When your patient clicks: a loud clicking sound as a key sign to the diagnosis.

A 19-year-old male patient was referred by his general practitioner with a new 'cardiac murmur'. For 1 week, he had been able to provoke a clicking sound, which was in time with his heart beat and originated from his chest. The physical examination and laboratory tests were normal. The sound was initially interpreted as most likely due to a valve condition such as mitral valve prolapse, but a transthoracic echocardiogram was normal. A cardiac CT was obtained, which showed left-sided ventral pneumothorax.The Hamman's sign is a loud precordial pulse synchronous sound, which is often postural. It is pathognomonic for left-sided pneumothorax or pneumomediastinum. Hamman's sign as a presenting symptom is rare, but if present is key to diagnosis. The awareness of rare clinical findings is important and will prevent unnecessary diagnostic tests.

Induction ovens and electromagnetic interference: what is the risk for patients with implantable cardioverter defibrillators?

Electromagnetic fields may interfere with normal implantable cardioverter defibrillator (ICD) function. Although the devices are effectively shielded and use exclusively bipolar leads, electromagnetic interference (EMI) remains a concern when patients are exposed to several household appliances. The aim of this study was to evaluate potential EMI risk of induction ovens, which are increasingly common in private households. In vitro measurements of an induction oven for private households GK 43 TI (V-Zug, Inc., Zug, Switzerland) showed that heating is regulated by increasing operating time from level 1 (100 ms/sec) to 5 (continuous operation). From levels 5 to 9 the magnetic field increases. Nineteen patients with left-sided implants of single- and dual-chamber ICD systems (8 Medtronic, 7 Guidant, and 4 St. Jude Medical) (18 males, 1 female), age (mean +/- SEM) 58 +/- 3 years, were included in this study. All patients were examined in standing position, bent over the cooking pot (minimal distance to the induction coil 25 cm), and with the cooking pot put eccentrically over the induction field at three different cooking levels (level 2, 5, and 9). The tests were repeated touching the cooking pot with one hand. Ventricular sensitivity was left unchanged. Ventricular tachycardia therapies were turned off in Medtronic and Guidant devices and ventricular sensing was continuously monitored in St. Jude Medical devices during testing. Interrogation of the devices after exposure did not show any inappropriate tachycardia detection, oversensing, or reprogramming. In conclusion, ICD patients can be reassured that EMI is unlikely to affect their devices if induction ovens are used in their kitchens.

Double aortic and pulmonary valves: An artifact generated by ultrasound refraction.

Echocardiography is an essential diagnostic tool for the investigation of the cardiovascular system. However, the nature of the ultrasound beam may lead to artifacts such as doubling of cardiac structures because of refraction. Here we present two illustrative cases showing doubling of the aortic ring and double regurgitation through the pulmonary valve. Doubling by refraction is different from other artifacts generating double images, such as mirroring of the ultrasound beam (eg, by prosthetic valves). Anatomic structures between the transducer and the heart such as the pleura, pericardium, or rib cartilage may induce refraction of the ultrasound beam resulting in doubling of cardiac structures. The resulting doubling of anatomic structures must not be misdiagnosed.