Biomedical subjects

Richard Fakin

Publications and source records attributed to Richard Fakin.

3 recordsLinked to original sources

PubMed2006

Long-term neurocognitive function after mechanical aortic valve replacement.

BACKGROUND: Mechanical aortic valves are a possible source of microemboli potentially causing cerebral injury. Therefore, the long-term impact of mechanical aortic valve replacement on neurocognitive function is uncertain. METHODS: In this prospective, contemporary study, we followed 32 consecutive patients (aged 51 +/- 8 years; range, 38 to 70; EuroSCORE [European System for Cardiac Operative Risk Evaluation] 4.4 +/- 1.7) undergoing isolated aortic valve replacement with a mechanical prosthesis. A cohort of age- and sex-matched patients (n = 28, aged 50 +/- 7 years) served as nonsurgical controls. After aortic valve replacement, neurocognitive function was serially reevaluated at 7-day (n = 32), 4-month (n = 31), and 3-year (n = 29) follow-up. Neurocognitive function was measured by means of P300 auditory evoked potentials. RESULTS: Before the operation, P300 peak latencies were comparable between surgical patients (361 +/- 32 ms) and nonsurgical controls (365 +/- 33 ms, p = 0.783). In patients undergoing aortic valve replacement, P300 peak latencies were prolonged 7 days after surgery (380 +/- 32 ms) as compared with before the operation (361 +/- 32 ms, p < 0.0001) and as compared with nonsurgical controls (364 +/- 34 ms, p = 0.002). At 4-month (369 +/- 30 ms, p = 0.752) and 3-year (370 +/- 31 ms, p = 0.825) follow-up, P300 peak latencies normalized as compared with before operation and as compared with nonsurgical controls (4-month follow-up 363 +/- 31 ms, p = 0.832; 3-year follow-up 366 +/- 32 ms, p = 0.432). We found no difference in patients with different valve types. CONCLUSIONS: Despite previous assumptions based on the potential occurrence of microemboli in patients with mechanical valves, mechanical aortic valve replacement has no adverse long-term impact on neurocognitive function. This finding is only valid for patients with a comparable age range undergoing isolated aortic valve replacement.

Adult↗

PubMed2006

Neuronal injury after repeated brief cardiac arrests during internal cardioverter defibrillator implantation is associated with deterioration of cognitive function.

To determine the degree of neurocognitive dysfunction after placement of internal cardioverter defibrillators (ICD) and its relationship to the extent of neuronal injury, we studied 42 patients undergoing ICD (n = 21) or pacemaker (PM) insertion (control patients, n = 21). The Mini Mental State Examination, the Trailmaking A test and the forward and backward Digit Span tests were used and P300 latencies were determined preoperatively and postoperatively. Serum neuron-specific enolase (NSE) was determined before and at the end of, as well as 2, 6, and 24 h after surgery. Preoperatively, PM patients scored worse in the Digit Span backward and the Trailmaking tests and showed prolonged P300 latencies. Postoperatively, the Digit Span backward scores declined and NSE levels increased only in the ICD group (P < or = 0.05). The difference between preoperative and postoperative Digit Span backward scores correlated with the increase in serum NSE levels (r2 = 0.3, P < or = 0.05). Moreover, P300 latencies increased in 13 of 17 ICD patients, but decreased in 7 of 10 PM patients (P < or = 0.05). PM patients even improved in the Trailmaking test (P < or = 0.05). Neuronal injury from even brief periods of global brain ischemia seems to be associated with deteriorating neurocognitive function.

Aged↗

PubMedDate not supplied

Neurocognitive function in patients with ventricular assist devices: a comparison of pulsatile and continuous blood flow devices.

The effect of successful ventricular assist device (VAD) implantation on neurocognitive function in terminal heart failure is uncertain. Additionally, the different impact of continuous versus pulsatile blood flow devices is unknown. A total of 29 patients (mean age 53 years), surviving implantation of a ventricular assist device as bridge to transplantation were prospectively followed (continuous flow: Micromed DeBakey, n = 11; pulsatile flow: Thoratec and Novacor, n = 18). Normative data were obtained in 40 age- and sex-matched healthy subjects (mean age 54 years). Neurocognitive function was objectively measured by means of cognitive P300 auditory evoked potentials before operation (baseline), at intensive care unit (ICU) discharge, and at the 8-week and 12-week follow-up. Before implantation of the VAD, cognitive P300 evoked potentials were impaired (prolonged) compared with age- and sex-matched healthy subjects (p < 0.001). After successful VAD implantation, P300 evoked potentials markedly improved compared with before operation (ICU discharge, p = 0.007; 8-week follow-up, p = 0.022; 12-week follow-up, p < 0.0001). Importantly, there was no difference between continuous and pulsatile VADs (before operation, p = 0.676; ICU discharge, p = 0.736; 8-week follow-up, p = 0.911 and 12-week follow-up, p = 0.397; respectively). Nevertheless, P300 peak latencies did not fully normalize at 12-week follow-up compared with healthy subjects (p = 0.012). Successful VAD implantation improves neurocognitive impairment in patients with terminal heart failure. Importantly, this effect is independent of the type of VAD (pulsatile vs. continuous blood flow).

Austria↗