Delayed posterior wall (PW) peak in the detection of PW asynergy was studied by M-mode echocardiography in 53 patients with angiographically proven PW aneurysm, hypokinesis and normal PW. The timing of the PW peak was evaluated by the intervals between (1) the aortic valve closure (Ac) and the PW peak, and (2) the R wave of the electrocardiogram and the PW peak (R-peak). The PW excursion predic...

The hot gases produced by the internal combustion engines passes through the exhaust valve and causes high temperatures in the exhaust valve and its seat. To avoid damaging the exhaust valve, heat must be transferred from the valve to its seat during the contact they make at the opening and closing cycle. Heat transfer rate from the exhaust valve to its seat is a function of many factors. One o...

Background Accurate measurement of maximal aortic root dimensions is important for informed decision making on the timing/ nature of aortic valve replacement surgeries in pediatric patients. Currently, the observer manually measures the following metrics to quantify maximum aortic root dimensions: 1) Cusp to Commisure (Cu-Co), and 2) Cusp to Cusp (Cu-Cu) lengths. This introduces significant int...

In a 69 year old woman with a "sticking" Björk-Shiley mitral prosthesis, the diagnosis was suggested by both the two-dimensional and the Doppler ultrasound examinations. In particular, the findings of early diastolic paradoxic septal motion, intermittent delayed opening of the prosthetic disc and variable timing of the onset of mitral valve inflow were believed to be diagnostic of a sticking ti...

A new type of apparatus for the production of single bubbles of adjustable size is presented. A single bubble is generated by injecting a short burst of gas into a liquid channel flow. The radius of the bubble can be varied continuously from 300 mm up to a 3 mm by adjusting the timing of a valve injecting the gas. The device works also in liquids with variable pressure and can be microcomputer ...