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OBJECTIVES Healthcare systems worldwide have been overburdened by the coronavirus disease 2019 (COVID-19) outbreak. Accordingly, hospitals had to implement strategies to profoundly reshape both non-COVID-19 medical care and surgical activities. Knowledge about the impact of the COVID-19 pandemic on cardiac surgery practice is pivotal. The goal of the present study was to describe the changes in cardiac surgery practices during the health emergency at the national level. METHODS A 26-question web-enabled survey including all adult cardiac surgery units in Italy was conducted to assess how their clinical practice changed during the national lockdown. Data were compared to data from the corresponding period in 2019. RESULTS All but 2 centres (94.9%) adopted specific protocols to screen patients and personnel. A significant reduction in the number of dedicated cardiac intensive care unit beds (−35.4%) and operating rooms (−29.2%), along with healthcare personnel reallocation to COVID departments (nurses −15.4%, anaesthesiologists −7.7%), was noted. Overall adult cardiac surgery volumes were dramatically reduced (1734 procedures vs 3447; P, The coronavirus disease 2019 (COVID-19) pandemic is the world’s largest infectious disease crisis in the last 100 years.

Background and aim:Endocarditis after Bentall procedure is a rare but severe complication. Infection usually involves the prosthesis, the annulus, and can lead to pseudoaneurysm or mediastinitis. Surgery in these patients is a challenge but conservative therapy, sometime preferred because of prohibi

This paper presents the results of a two years project led and funded by Eni from 2008 to 2010 with the aim of supporting the development and experimentation of innovative technology for environmental monitoring. The problem addressed is the precise estimate of possible altimetric variations of the seabed through long-term monitoring. The selected methodology consists in the application of repeat-track interferometry to high-resolution, high-frequency sonar data collected from an AUV during repeated surveys of a seafloor area of interest. The paper describes the experimental measurements conducted at sea, the SAS and interferometry methodologies developed, and the results obtained on artificial objects sitting on the seabed. The quality of the achieved focusing is analyzed. The achieved repeat-pass SAS interferograms are shown and analyzed. The coherence along time of the particular kind of seabed (silty sand) characterizing the experimental area is presented and the utility of artificial reflectors for long-term SAS interferometry is discussed.

The in vivo evaluation of prosthetic device performance is often difficult, if not impossible. In particular, in order to deal with potential problems such as thrombosis, haemolysis, etc., which could arise when a patient undergoes heart valve replacement, a thorough understanding of the blood flow dynamics inside the devices interacting with natural or composite tissues is required. Numerical simulation, combining both computational fluid and structure dynamics, could provide detailed information on such complex problems. In this work, a numerical investigation of the mechanics of two composite aortic prostheses during a cardiac cycle is presented. The numerical tool presented is able to reproduce accurately the flow and structure dynamics of the prostheses. The analysis shows that the vortical structures forming inside the two different grafts do not influence the kinematics of a bileaflet valve or the main coronary flow, whereas major differences are present for the stress status near the suture line of the coronaries to the prostheses. The results are in agreement with in vitro and in vivo observations found in literature.

The integrated study, concerning the experimental observations, was performed during the oceanographic cruises on-board the two NURC research vessels, in the period between 2008 and 2010 in the Marine Protected Area of Cinque Terre (North-West Mediterranean Sea, Italy). The aim of the research is to describe the environmental features using both hydrological parameters and AUV navigation tracks, acquired respectively by a multi-parametric platform (MEDUSA) and AUV MUSCLE. The innovative contribution of this work is the possibility to evaluate the bottom stream without direct current measurements, but using the navigation data recorded by AUV. This work is a complementary analysis to environmental support of the ENI S.p.A. Exploration and Production Division project.

Age over 70 years and critical stenosis of the left main coronary artery trunk are two situations in which the use of the internal mammary artery has been questioned. Because the coexistence of these two conditions is increasingly seen, we reviewed our experience with 53 patients 70 years of age or older that underwent myocardial revascularization for left main disease. In 17 patients, the left anterior descending coronary artery was grafted with the left internal mammary artery whereas the 36 remaining patients were exclusively revascularized by means of saphenous vein conduits. There was no significant difference in postoperative mortality or morbidity between the two patient groups. We conclude that elderly patients with left main disease should be offered the benefits of a mammary artery graft provided they are hemodynamically stable.

Synthetic Aperture Radar (SAR) and Sonar (SAS) systems provide high resolution reflectivity maps of the imaged scene by coherently combining the echoes collected along a virtual array of receivers. A peculiarity of SAS systems is that the echoes are often collected by moving a short real array of hydrophones to avoid range ambiguity. In this paper we present a modification of the standard wavenumber focusing algorithm widely used in SAR data processing to make it suitable for focusing bi-static SAS data. An autofocusing technique is then exploited to estimate and compensate for the deviation of the platform trajectory from the rectilinear one.

Appraisal of the medium-term results of isolated aortic valve replacement with a CarboMedics mechanical prosthesis.We assessed the clinical data of 195 consecutive patients (mean age 59.7+/-10.9 years) operated on between January 1992 and June 2000. Valve disease consisted of aortic stenosis regurgitation in 94 patients (48.2%), isolated aortic failure in 57 (29.2%) and isolated stenosis in 44 (22.6%). One hundred and four patients were in NYHA functional class III and 25 in NYHA functional class IV Follow-up was by telephone interview to 100% of the patients (average follow-up 39+/-20 months).The operative mortality was 3.6% (5% in the period January 1992-December 1995, 1.3% in the period January 1996-June 2000). Sixteen deaths occurred in the long term. Thus, the actuarial survivals at 36 and 72 months were 92+/-7% and 82+/-16% respectively. In the group of survivors, 139 patients (81%) were in NYHA class 1,26 (15%) in NYHA class II, and 7 (4%) in NYHA class III. The freedom from embolic events was 96+/-3.7% and that from hemorrhagic events was 90+/-9.4%. All the events occurred during the first 36 months; none of the patients developed infections or periprosthetic leaks.At the medium term, the CarboMedics mechanical valve prosthesis appears to be reliable, with an actuarial survival, quality of life and incidence of morbidity comparable to those reported for other types of second-generation mechanical prostheses.

This report describes the different clinical and instrumental manifestations of coronary ischemia in a patient with left main coronary artery atresia. Exercise test and thallium-201 perfusion scintigraphy during isometric exercise test were negative for angina and electrocardiographic changes. Conversely, dipyridamole infusion caused severe angina, marked ST-segment changes and diffuse thallium-201 uptake abnormalities. This peculiar anatomical condition offers the opportunity of high-lighting the role played by the microcirculation in determining myocardial ischemia.

We report the case of a 23-year-old man who was admitted to our Division with the diagnosis of pericardial lipoma. Chest X-ray, echocardiography and magnetic resonance imaging failed to reveal an anterior diaphragmatic hernia containing a small part of the stomach with a big prehernial lipoma that were found at surgery. We believe that in all cases of suspected pericardial lipoma a diaphragmatic hernia should be expected.

To establish whether the adaptation to ischemia observed in humans during percutaneous transluminal coronary angioplasty (PTCA) after repeated balloon inflations, i.e. a clinical correlate of ischemic preconditioning, is preserved in elderly patients.We studied 53 consecutive patients undergoing successful angioplasty for an isolated stenosis of a major epicardial coronary artery. On the basis of age, patients were separated into terciles: patients in the lower and middle terciles were grouped together (Group 1, adult patients, n = 24, mean age 50 +/- 6 years) and compared with those in the upper tercile (Group 2, elderly patients, n = 29, mean age 68 +/- 3 years). Intracoronary electrocardiogram was obtained at the end of the first two balloon inflations. Collateral recruitment during repeated balloon inflations was assessed by using an intracoronary Doppler guide wire (23 patients) or by using an intracoronary pressure guide wire (30 patients).In Group 1, ST-segment changes during the second inflation were significantly less than those at the end of the first inflation (6 +/- 3 vs 13 +/- 5 mm, p0.001). Similarly, in Group 2, ST-segment changes during the second inflation were significantly less than those at the end of the first inflation (6 +/- 4 vs 13 +/- 6 mm, p0.001). In both groups, collateral recruitment did not change from the first inflation to the second inflation (p = 0.1).Our study confirms that adaptation to ischemia during repeated balloon inflations in the setting of PTCA is independent of collateral recruitment and, therefore, is mainly due to ischemic preconditioning. More importantly, our study indicates that ischemic preconditioning is preserved in elderly patients.

This article describes a new aortic Dacron conduit that has been designed for use in all types of surgery of the aortic root. Its use is aimed at facilitating the surgical procedure and obtaining a natural anatomical configuration of the aortic root.The modified Dacron conduit is obtained by adding a smaller piece of Dacron tube that is resilient in the horizontal plane to one end of a standard Dacron conduit. Upon implantation, this small piece of Dacron conduit will stretch in the horizontal plane creating pseudosinuses and a new sinotubular junction. This modified conduit has been used in 4 cases for a Bentall operation in association with a mechanical or a biological valve, in 4 cases in a Yacoub type of valve sparing procedure and in 1 case in a David type I of valve sparing procedure. All patients had aortic root aneurysm with severe aortic regurgitation. There were 6 males and 3 females with a mean age of 61 +/- 16 years. In most cases a 28 mm Dacron conduit was used.All surgery was carried out without mortality or morbidity. The creation of pseudosinuses was confirmed intraoperatively by visual inspection. Transesophageal echocardiography in patients who had undergone the Bentall operation showed a normally functioning valve prosthesis with a suitably shaped aortic root. In patients who had undergone the valve sparing procedures it showed a competent aortic valve, the creation of pseudosinuses of normal shape and depth, and the presence of a well defined sinotubular junction. Angiography confirmed that the prosthetic aortic root perfectly resembled the normal root anatomy.This modified new aortic root conduit appears to perfectly reproduce a normal root anatomy without the need of modifying the original techniques.

Coronary artery bypass grafting is reported to have a higher (2-3 times) mortality in women than in men, most likely due to older age, higher incidence of hypertension, diabetes mellitus, hypercholesterolemia, obesity, angina and preoperative myocardial infarction, smaller diameter of coronary arteries, and smaller body surface area.From January 1992 to December 1997, 347 female and 2098 male patients were submitted to isolated coronary artery bypass grafting. For both groups were considered: a) clinical presentation (age, height, weight, body surface area, NYHA and CCS functional classes, incidence of preoperative myocardial infarction); b) risk factors for cardiovascular diseases (diabetes mellitus, smoking habit, dyslipidemia, hypertension, familiarity); c) concomitant diseases (obesity, chronic obstructive pulmonary disease, peripheral vascular disease, thyroid dysfunction); d) hemodynamic and anatomical data (extent of coronary artery disease, diameter of coronary arteries, left ventricular function); e) surgical procedure (number and type of grafts used, urgent procedures, incidence of redo procedures). Early (up to 30 days after surgery) results were evaluated in terms of complications and mortality.On admission, women were older than men (p = 0.0001), were shorter (p0.0001), weighed less (p0.0001), and had a smaller body surface area (p0.0001); they had more severe angina (p = 0.002), diabetes mellitus (p = 0.002), hypercholesterolemia (p = 0.003), thyroid dysfunction (p0.0001), their coronary arteries were smaller (left anterior descending artery, p = 0.05; obtuse marginal branch, p = 0.008; diagonal branch, p = 0.01), and had less grafts implanted at surgery (p = 0.02). There was no difference between women and men in the use of the internal thoracic artery. Women did not have a higher mortality than men (4.6 vs 3.2%). Uni- and multivariate analysis did not show extraoperative risk factors for women; for men older age (p = 0.005) and poor left ventricular function (p = 0.01) were independent predictive factors of operative mortality.In spite of what is suggested by the literature, coronary artery bypass grafting does not have a significant higher operative risk for women than men, probably due to surgical technique refinements and extensive use of the internal thoracic artery.

The incidence of coronary artery disease in patients with dextrocardia associated with situs inversus is similar to that of the general population: Nevertheless, there are few papers regarding surgical myocardial revascularization in these patients.We report two patients with dextrocardia and situs inversus who underwent myocardial revascularization by means of coronary artery bypass grafting, with the right internal mammary artery to the left anterior descending coronary artery in one case and with the left internal mammary artery as a free graft to the left anterior descending coronary artery associated with the repair of an aneurysm of the right coronary sinus of Valsalva in the second patient.There were no surgical complications; the patients were discharged on the 4th and 7th postoperative days, respectively. They are alive and well after 24 and 60 months of follow-up respectively.This report suggests that durable myocardial revascularization in dextrocardia with situs inversus can be successfully achieved with right or left mammary artery bypass grafting to the left anterior descending coronary artery. The advantage of using an in situ mammary artery is discussed.

Between June 1958 and December 1991, 315 patients (217 male and 98 female, mean age = 17.8 +/- 5.5 years) affected by pectus excavatum (PE) were surgically treated. Most of the patients required operation for aesthetic reasons only (299 patients; 95 percent). The grade of PE (Chin classification) was I in 72 patients, II in 152, and III in the remaining 91. The surgical technique consisted of a double transversal sternotomy at the level of the lowest and highest part of the depression associated with a longitudinal sternotomy. A wedge resection of the ribs was then performed and the sternum was fixed using a stainless steel strut molded into a seagull wing prosthesis. The strut was removed 12 months postoperatively. There were no operative mortalities. Four patients had sternal wound infection that was successfully treated. The mean follow-up was 15.8 years per patient and was 60 percent complete. From the aesthetic point of view, the postoperative results were excellent in 246 patients (78 percent), good in 57 (18 percent), and poor in 12 (4 percent). All subjective symptoms, when present, disappeared after surgery. The seagull wing prosthesis appears to be safe, easy to implant and to remove, and comfortable for the patient. This technique has shown good long-term results independently of type of deformity and patient age.

Chordal preservation during mitral valve replacement is thought to greatly preserve left ventricular function. Recently a stentless mitral valve (Biocor) became available for clinical use. It is a porcine mitral valve with the entire chordal apparatus, the sewing ring being reinforced by a bovine pericardial ring and the chordae being sutured together onto two pericardial patches. During a six months period, seven patients undergoing mitral valve replacement for mitral insufficiency (four cases), mitral stenosis (two cases) or mixed lesions (one case) received a stentless mitral valve. Their mean age was 66.3 +/- 4.8. The valve was implanted by suturing the pericardial patches onto the papillary muscles and the sewing ring onto the mitral annulus. Echocardiography control immediately after surgery showed good valve function. Three valves failed after a period of seven days, seven and 12 months respectively. The valve lesions were similar and consistent with an excessive tension on the chordae and on the valvular tissue. There were tears along the posterior annulus and at the level of the commissures, often accompanied by chordal rupture. Histology and scanning electron microscopy showed good integration of the prosthesis with the patients own tissues. There were areas of overgrowing tissue without endothelial cells especially in the area of papillary muscle -pericardial patch interaction. The remaining four patients continue to do well after a mean follow up of two years. The apparent excessive tension on the valve tissues leading to the premature failure of the prosthesis could be due to the variability in the distance between mitral annulus and papillary muscles.(ABSTRACT TRUNCATED AT 250 WORDS)

BACKGROUND Brief episodes of ischemia render the heart more resistant to subsequent ischemia; this phenomenon has been called ischemic preconditioning. In some animal species, myocardial preconditioning appears to be due to activation of ATP-sensitive K+ (KATP) channels. The role played by KATP channels in preconditioning in humans remains unknown. The aim of this study was to establish whether glibenclamide, a selective KATP channel blocker, abolishes the ischemic preconditioning observed in humans during coronary angioplasty following repeated balloon inflations. METHODS AND RESULTS Twenty consecutive patients undergoing one-vessel coronary angioplasty were randomized to receive 10 mg oral glibenclamide or placebo. Sixty minutes after glibenclamide or placebo administration, patients were given an infusion of 10% dextrose (8 mL/min) to correct glucose plasma levels or, respectively, an infusion of saline at the same infusion rate. Thirty minutes after the beginning of the infusion, both patient groups underwent coronary angioplasty. The mean values (+/- 1 SD) of ST-segment shifts on the surface 12-lead ECG and the intracoronary ECG were measured at the end of the first and second balloon inflations, both 2 minutes long. In glibenclamide-treated patients, the mean ST-segment shift during the second balloon inflation was similar to that observed during the first inflation (23 +/- 13 versus 20 +/- 8 mm, P = NS), and the severity of cardiac pain was greater (55 +/- 21 versus 43 +/- 23 mm on a scale of 0 to 100, P < .05). Conversely, in placebo-treated patients the mean ST-segment shift during the second inflation was less than that during the first inflation (9 +/- 5 versus 23 +/- 13 mm, P < .001), as was the severity of cardiac pain (15 +/- 15 versus 42 +/- 19 mm, P < .01). Blood glucose levels were significantly reduced 60 minutes after glibenclamide compared with those at baseline (53 +/- 9 versus 102 +/- 10 mg/100 mL, P < .001) in the glibenclamide group; however, before coronary angioplasty, blood glucose levels increased to 95 +/- 19 mg/100 mL, a value similar to that found in placebo group (96 +/- 11 mg/100 mL, P = NS). CONCLUSIONS In humans, ischemic preconditioning during brief repeated coronary occlusions is completely abolished by pretreatment with glibenclamide, thus suggesting that it is mainly mediated by KATP channels.

Cardiac suction has been previously demonstrated in the normal heart and in cardiac diseases characterized by a normal or reduced end-diastolic ventricular pressure. We report a patient with tight mitral stenosis and severe tricuspid regurgitation who provides the evidence of cardiac suction, despite the presence of increased end-diastolic pressures. The negative diastolic pressures observed in our patient appear to be related to the preservation of a vigorous contraction of both ventricles resulting in small end-systolic volumes. In this setting the elastic potential energy stored in the myocardium during each vigorous contraction is released during diastole, thus creating a negative pressure which sucks blood into the ventricles.

Between 1961 and 1985, 14 patients (9 males, 5 females; mean age 42.3 +/- 7.26 years) underwent surgery for excision of cardiac myxoma. Origin of the neoplasm was left atrium in all patients. In the last 7 cases diagnosis was obtained by echocardiographic examination. The clinical manifestations were dyspnea in 8 cases, palpitation in 5 and neurological symptoms in 3. One patient with concomitant mitral and aortic incompetence died on the 13th postoperative day because of low-output syndrome. All 13 operative survivors are alive and well without echocardiographic evidence of neoplastic recurrence at a follow-up ranging from 7 to 31 years. These results indicate a low incidence of recurrence with a complete tumor excision even without its extension to the normal atrial endocardium.

This case report describes a patient with massive pulmonary embolism and acute circulatory failure in whom transesophageal echocardiography permitted the diagnosis of thrombi in the main pulmonary truncus and in the right branch and guided intraoperatively the surgical embolectomy performed under simple venous inflow occlusion because of a contraindication to heparin administration. Transesophageal echocardiography seems to be a very helpful technique to diagnose promptly massive pulmonary embolism and a very useful tool at the time of operation to guide the embolectomy.

One hundred and fifty-three patients undergoing De Vega tricuspid annuloplasty, with or without other associated cardiac procedures between January, 1979, and June, 1987, were evaluated. There were 136 hospital survivors. The follow-up was 98.1% complete for a mean of 3.7 years/patient. Operative mortality was 11.1%; preoperative NYHA class and length of CPB were significant risk factors of perioperative mortality. The actuarial survival of operative survivors at 9 years was 73.5 +/- 11.8%. There were 7 late cardiac deaths among a total of 12 late deaths. Eleven patients required reoperation (2.1 +/- 0.6% patient-year). In seven patients it was necessary for recurrence of tricuspid regurgitation; six of these had also a mitral prosthesis malfunction or a periprosthetic leak. Residual tricuspid regurgitation was judged as mild, moderate or severe in 29.9%, 11.9% and 4.3% of the patients respectively. De Vega tricuspid annuloplasty is the method of choice for mild and moderate tricuspid insufficiency; in selected cases, with a more severe degree of regurgitation, better results could be achieved with a different surgical approach.

The possibility of achieving effective mechanical ventricular assistance without the need for thoracotomy provides great clinical advantages. Two in vitro systems were used to assess left ventricular unloading by means of a small-diameter cannula inserted retrograde into the left ventricle by cannulation of the femoral artery. This cannula is connected to the inlet of a centrifugal blood pump (CP) that delivers the blood into the controlateral femoral artery. Steady-flow test circulation was used to pump fluid in a closed loop from a reservoir through the test cannula back into the reservoir. Pressure drops over cannulae with inner diameters of 4, 5, 6, 7, and 8 mm at flows of 2, 2.5, 3 L/min, against a pressure of 60, 80, 100, and 120 mmHg were calculated. A stationary pressure drop of 120 mmHg was measured at a flow of 3 L/min through a 100 cm cannula with an inner diameter of 6 mm. The second system was a pulsatile mock circulation composed of an atrial and an arterial reservoir linked by a pneumatic prosthetic ventricle. This system was coupled with a 100 cm cannula, 6.1 mm inner diameter, which was passed across the outflow valve of the pulsatile prosthetic ventricle and connected to a CP. Fluid was withdrawn from the ventricle and pumped back into the arterial reservoir. Pulsatile pressure drop over the cannula was measured at different CP flows for increasing systolic ventricular pressure; heart unloading was quantified as a function of CP flow under baseline and failing conditions of the prosthetic left ventricle model. At a constant CP flow the pressure drop over the cannula increased with the pulsatility inside the ventricle. The work of the prosthetic ventricle was reduced by more than 50% when the CP pump was set to 3 L/min; at the same flow setting, when the situation of a failing left ventricle was simulated, the CP was able to take over all the work of the prosthetic ventricle, establishing a stationary flow and a 25% higher mean aortic pressure. This approach to left ventricular assistance may have significant clinical relevance.

Postoperative adhesions following open heart surgery enhance the risks and increase the time of subsequent reoperation. When possible, primary closure of the natural pericardium is recommended, particularly in those cases that are more likely to be reoperated upon. The use of a total artificial heart (TAH) as a bridge to transplantation makes reoperation mandatory. If the pleura is left open to accommodate the ventricles, the risk of adhesion is considerable. To address this question, gluteraldehyde-fixed pericardial allografts were evaluated in calves undergoing TAH replacement. Eight animals were implanted with 3 different types of TAHs and survived from 12 to 108 days (mean 52.8 +/- 14.5). The pericardial substitute was wrapped around the TAH and the vascular grafts and cuffs. Two different surgical techniques were evaluated. At the time of autopsy, the presence of adhesions and gross epicardial reaction was macroscopically characterized and classified according to a standardized scale. Bacterial cultures were taken and tissue submitted for histology. The animals implanted with pericardial allografts for periods greater than 3 weeks were observed to have greater adhesions than those implanted for periods less than 3 weeks (p = 0.006). Pericardial cultures were negative in all cases and neovascularization and fibroplasia of the underlying tissues occurred in all cases. Leukocyte infiltration was minimal in the shorter term implant animals. Degeneration of a portion of the pericardium occurred in only 2 cases after 90 days. Minor calcification of the artificial pericardium was noted, but only in the longer term implant animals. The artificial pericardium reduced adhesion, thus facilitating reoperation in implants lasting up to a month.(ABSTRACT TRUNCATED AT 250 WORDS)

This paper describes a procedure of cellular dissociation which allows the isolation of single cells from the human heart while preserving their integrity and physiological function necessary for electrophysiological studies in vitro. During open heart surgery, biopsies were obtained from the right atrium of the beating heart in 16 patients immediately before starting the extracorporeal circulation. The tissue was immediately placed in a cardioplegic solution at 4 degrees, and subsequently in a free-calcium solution at 20 degrees from 20' to 30'. It was then exposed to the proteolytic action of Collagenase type I and Protease type VII (Sigma Chemical Co., St Louis, USA) at 35 degrees for a maximum of 5 hours. The cells were finally transferred into a Tyrode solution at room temperature. With this method we obtained up to 70% of intact human myocytes, 40% of which calcium-tolerant. The subsequent electrophysiological studies performed showed that the cells maintained their morphological and physiological properties.

The effect of platelet activating factor (PAF) on three mechanical [maximal mechanical tension (Pmax); time to peak tension; maximal rate of rise of tension (+dP/dt)] and four electrical [action potential duration (APD); resting membrane potential; overshoot; maximum rate of depolarization] parameters of cardiac function was studied on fragments of isolated human cardiac papillary muscle. 20 specimens of small tissue fragments excised from the left ventricle by open heart surgery were challenged with various doses of synthetic PAF (10––10––10––6M). PAF, but not its biologically inactive 2-lyso-derivative (lyso-PAF), induced a biphasic dose-dependent effect, characterized by a transient positive effect on inotropism (increased Pmax, + dP/dt) and of APD, followed by a marked, prolonged negative effect on both inotropism (decreased Pmax, time to peak tension, + dP/dt) and APD. No changes in resting membrane potential, overshoot and maximum rate of depolarization were detected after PAF challenge. Propranolol (2 × 10––7M) completely prevented the positive inotropic effect suggesting a stimulation of β-receptors, possibly exerted by endogenous catecholamines. In-domethacin (1 × 10––4M) did not modify the initial positive effect, but markedly reduced the subsequent negative effect induced by PAF on inotropism. These findings are consistent with the interpretation that the effect of PAF on the inotropism is related to liberation of cyclooxygenase-derived metabolites.

This study was undertaken to evaluate the myocardial preservation obtained by adding a Ca++ channel blocker, nifedipine, to cold potassium cardioplegia (4 mcg/Kg/L) in 24 patients undergoing coronary artery surgery. They were randomly divided into a treated (N) and a control (C) group. Significant differences between the two groups were noted in the cardiac arrest time (p less than 0.001), in the mechanical recovery mode (p less than 0.01) and in the inotropic support needed (p less than 0.01). Cardiac index increased significantly in group N but decreased in group C (p less than 0.01). Peripheral delta P/delta t and endocardial viability ratio (EVR) decreased in both groups. Coronary sinus and serum CK and CK-MB release were significantly lower in the treated group. ECG ischaemic changes occurred in 8 patients in group C but only in 1 case in group N (p less than 0.001). Arrhythmias occurred in 3 cases in group C (p less than 0.05). The incidence of perioperative myocardial infarction was not significant (2 cases in group C). These data suggest that nifedipine can protect the myocardial cell from ischaemic injury without depressing myocardial contractility or AV conduction.

This study was undertaken to evaluate the myocardial preservation obtained by adding a Ca++ channel blocker, nifedipine, to cold potassium cardioplegia (4 mcg/Kg/L) in 24 patients undergoing coronary artery surgery. They were randomly divided into a treated (N) and a control (C) group. Significant differences between the two groups were noted in the cardiac arrest time (p less than 0.001), in the mechanical recovery mode (p less than 0.01) and in the inotropic support needed (p less than 0.01). Cardiac index increased significantly in group N but decreased in group C (p less than 0.01). Peripheral delta P/delta t and endocardial viability ratio (EVR) decreased in both groups. Coronary sinus and serum CK and CK-MB release were significantly lower in the treated group. ECG ischaemic changes occurred in 8 patients in group C but only in 1 case in group N (p less than 0.001). Arrhythmias occurred in 3 cases in group C (p less than 0.05). The incidence of perioperative myocardial infarction was not significant (2 cases in group C). These data suggest that nifedipine can protect the myocardial cell from ischaemic injury without depressing myocardial contractility or AV conduction.

After the first pioneering clinical attempts with blood pumps by Dr. Cooley in 1969 and 1981 [1, 2], continued research with animal implantations has led to improvement in the design, techniques of fabrication, choice of materials, and reliability of mechanical components of blood pumps, which have reached a level of practicality high enough for limited clinical application.