by Isaac Asimov
Cora looked anxious, then unzipped his uniform. “Sit up,” she said. “Please try to sit up.” She slipped an arm under his shoulders and struggled him upright, then pulled the uniform down over his shoulders with practiced gentleness.
“I’ll take care of it for you,” she said. “—And thank you. It seems foolishly inadequate, but thank you.”
Grant said, “Well, do the same for me sometime, will you? Help me into my chair, will you?”
He struggled to his feet now, Cora helping him on one side, Michaels on the other. Duval, after one glance at them, had limped to the window.
Grant said, “Now what happened?”
Michaels said, “An arterioven … Well, put it this way. An abnormal connection existed between an artery and a small vein. It happens sometimes, usually as the result of physical trauma. It happened to Benes at the time he was hurt in the car, I suppose. It represents an imperfection, a kind of inefficiency, but in this case not a serious one. It’s microscopic; a tiny eddy.”
“A tiny eddy. This!”
“On our miniaturized scale, of course, it’s a gigantic whirlpool.”
“Didn’t it show up on your charts of the circulatory system, Michaels?” asked Grant.
“It must have. I could probably find it here on the ship’s chart, if I could magnify it sufficiently. The trouble is my initial analysis had to be made in three hours and I missed it. I have no excuse.”
Grant said, “All right, it just means some lost time. Plot out an alternate route and get Owens started. What’s the time, Owens?” He looked at the Time Recorder automatically as he asked. He read: 52, and Owens said, “Fifty-two.”
“Plenty of time,” said Grant.
Michaels was staring at Grant with raised eyebrows. He said, “There’s no time, Grant. You haven’t grasped what’s happened. We’re finished. We’ve failed. We can’t get to the clot anymore, don’t you understand? We must ask to be removed from the body.”
Cora said in horror, “But it will be days before the ship can be miniaturized again. Benes will die.”
“There’s nothing to be done. We’re heading into the jugular vein now. We can’t go back through the fissure for we couldn’t buck that current, even when the heart is in the diastolic stage, between beats. The only other route, the one in which we follow the venous current, leads through the heart, which is clear suicide.”
Grant said, numbly, “Are you sure?”
Owens said, in a cracked, dull voice, “He’s right, Grant. The mission has failed.”
CHAPTER 10
Heart
A modified hell had broken loose in the control tower. The blip indicating the ship had scarcely changed position on the overall screen but the coordinate pattern had been critically altered.
Carter and Reid turned at the sound of a monitor signal.
“Sir,” the face on the screen was agitated. “Proteus off course. They’ve picked up a blip in Quadrant 23, Level B.”
Reid rushed to the window overlooking the mapping room. There was nothing to see at that distance, of course, except heads bent over the charts in quite obviously electric concentration.
Carter reddened. “Don’t give me that quadrant stuff. Where are they?”
“In the jugular vein, sir, heading for the superior vena cava.”
“In a vein!” For a moment, Carter’s own veins were in alarming evidence. “What in the world are they doing in a vein? Reid!” he thundered.
Reid hurried to him. “Yes, I heard.”
“How did they get into a vein?”
“I’ve ordered the men at the chart to try to locate an arterio-venous fistula. They’re rare and not easy to find.”
“And what …”
“Direct connection between a small artery and a small vein. The blood seeps over from the artery to the vein and …”
“Didn’t they know it was there?”
“Obviously not. And Carter …”
“What?”
“It may have been a pretty violent affair on their scale. They may not have survived.”
Carter turned to the bank of television screens. He punched the appropriate button. “Any new messages from the Proteus?”
“No, sir,” came the quick answer.
“Well, get in touch with them, man! Get something out of them! And put it through to me directly.”
There was an agonizing wait while Carter held his chest motionless for the space of three or four ordinary breaths. The word came through. “Proteus reporting, sir.”
“Thank God for so much,” muttered Carter. “State the message.”
“They’ve passed through an arterio-venous fistula, sir. They cannot return and they cannot go ahead. They ask leave to be brought out, sir.”
Carter brought both fists down upon the desk. “No! By thunder, no!”
Reid said, “But general, they’re right.”
Carter looked up at the Time Recorder. It stood at 51. He said, through trembling lips, “They have fifty-one minutes and they’ll stay there fifty-one minutes. When that thing there reads zero, we take them out. Not a minute before, unless the mission is accomplished.”
“But it’s hopeless, darn it. God knows how weakened their ship is. We’ll be killing five men.”
“Maybe. That’s the chance they take and that’s the chance we take. But it will be firmly recorded that we never gave up as long as the smallest mathematical chance of success remained.”
Reid’s eyes were cold and his very mustache bristled. “General, you’re thinking of your record. If they die, sir, I’ll testify that you kept them in past reasonable hope.”
“I’ll take that chance, too,” said Carter. “Now you tell me—you’re in charge of the medical division—why can’t they move?”
“They can’t go back through the fistula against the current. That’s physically impossible no matter how many orders you give. The gradation of blood pressure is not under Army control.”
“Why can’t they find another route?”
“All routes from their present position to the clot lead through the heart. The turbulence of the heart passage would smash them to kindling in an instant and we can’t take that chance.”
“We …”
“We can’t, Carter. Not because of the lives of the men, though that’s reason enough. If the ship is smashed, we’ll never get all of it out and eventually its fragments will de-miniaturize and kill Benes. If we get the men out now we can try operating on Benes from outside.”
“That’s hopeless.”
“Not as hopeless as our present situation.”
For a moment, Carter considered. He said, quietly, “Colonel Reid, tell me—without killing Benes, how long can we stop his heart?”
Reid stared. “Not for long.”
“I know that. I’m asking you for a specific figure.”
“Well, in his comatose state, and under hypothermic chilling, but allowing for the shaky condition of his brain, I would say no more than sixty seconds. —On the outside.”
Carter said, “The Proteus can plow through the heart in less than sixty seconds, can’t it?”
“I don’t know.”
“They’ll have to try, then. When we’ve eliminated the impossible, whatever remains, however risky, however slim a hope, is what we’re going to try. —What are the problems involved in stopping the heart?”
“None. It can be done with a bare bodkin, to quote Hamlet. The trick will be to start it again.”
“That, my dear colonel, is going to be your problem and your responsibility.” He looked at the Time Recorder, which read 50. “We’re wasting time. Let’s get on with it. Get your heart men into action and I’ll have the men on the Proteus instructed.”
The lights were on within the Proteus. Michaels, Duval and Cora, looking disheveled, clustered about Grant.
Grant said, “And that’s it. They’re stopping Benes’ heart by electric shock at the moment of our approach and they’ll start it again
when we emerge.”
“Start it again!” exploded Michaels. “Are they mad? Benes can’t take that in his condition.”
“I suspect,” said Grant, “they consider it the only chance the mission has of succeeding.”
“If that’s the only chance, then we’ve failed.”
Duval said, “I’ve had experience with open-heart surgery, Michaels. It may be possible. The heart is tougher than we think. —Owens, how long will it take us to pass through the heart?”
Owens looked down from the bubble. “I’ve been figuring out just that, Duval. If we have no delays, we can do it in from fifty-five to fifty-seven seconds.”
Duval shrugged. “We’d have three seconds to spare.”
Grant said, “Then we’d better get on with it.”
Owens said, “We’re drifting with the current toward the heart right now. I’ll shift the engines into high. I need to test them, anyway. They took a bad beating.”
A muted throb rose somewhat in pitch and the sensation of forward motion overlay the dull, erratic trembling of Brownian motion.
“Lights out,” said Owens, “and we’d better relax while I baby this thing along.”
And with lights out, all drifted to the window again—even Michaels.
The world about them had changed completely. It was still blood. It still contained all the bits and pieces, all the fragments and molecular aggregates, the platelets and red blood corpuscles, but the difference—the difference …
This was the superior vena cava now, the chief vein coming from the head and neck, its oxygen supply consumed and gone. The red blood corpuscles were drained of oxygen and now contained hemoglobin itself, not oxyhemoglobin, that bright red combination of hemoglobin and oxygen.
Hemoglobin itself was a bluish-purple, and in the erratic reflection of the miniaturized light waves from the ship, each corpuscle glittered in flashes of blue and green with a frequently interspersed purple. All else took on the tinge of these unoxygenated corpuscles.
The platelets slid by in shadow and twice the ship passed—at a most grateful distance—the ponderous heavings of a white blood cell, colored now in greenish-tinged cream.
Grant looked at Cora’s profile once more with almost worshipful reverence, lifted, as it was, and looking infinitely mysterious in shadowy blue. She was the ice-queen of some polar region lit by a blue-green aurora, Grant thought quixotically, and suddenly found himself empty and yearning.
Duval murmured, “Glorious!” —But it was not at Cora that he was looking.
Michaels said, “Are you ready, Owens? I’m going to guide you through the heart.”
He moved to his charts and put on a small overhead light that instantly dimmed the murky blue that had just filled the Proteus with mystery.
“Owens,” he called. “Heart chart A-2. Approach. Right atrium. You have it?”
“Yes, I have.”
Grant said, “Are we at the heart already?”
“Listen for yourself,” said Michaels, testily. Don’t look. Listen!”
An unbreathing silence fell upon those within the Proteus.
They could hear it—like the distant boom of artillery. It was only a rhythmic vibration of the floor of the ship, slow and measured, but growing louder. A dull thud, followed by a duller; a pause, then a repetition, louder, always louder.
“The heart!” said Cora. “It is.”
“That’s right,” said Michaels, “slowed a great deal.”
“And we don’t hear it accurately,” said Duval, with dissatisfaction. The sound waves are too immense in themselves to affect our ear. They set up secondary vibrations in the ship but that’s not the same thing. In a proper exploration of the body …”
“At some future time, doctor,” said Michaels.
“It sounds like cannon,” said Grant.
“Yes, but it lays down quite a barrage; two billion heartbeats in threescore years and ten,” said Michaels. “More.”
“And every beat,” added Duval, “is the thin barrier separating us from Eternity, each giving us time to make our peace with …”
“These particular beats,” said Michaels, “will send us straight to Eternity and give us no time at all. Shut up, all of you. —Are you ready, Owens?”
“I am. At least I’m at the controls and I’ve got the chart before me. But how do I find my way through this?”
“We can’t get lost, even if we try. —We’re in the superior vena cava now, at the point of junction with the inferior. Got it?”
“Yes,”
“All right. In seconds, we’ll be entering the right atrium, the first chamber of the heart—and they had better stop the heart, too. Grant, radio our position.”
Grant was momentarily lost to all else in his fascination with the view ahead. The vena cava was the largest vein in the body, receiving in the final stretch of its tube all the blood from all the body but the lungs. And as it gave way to the atrium, it became a vast resounding chamber, the walls of which were lost to sight so that the Proteus seemed to be within a dark, measureless ocean. The heart was a slow, terrifying pound now, and at each steady thud, the ship seemed to lift and tremble.
At Michaels’ second call, Grant snapped back to life and turned to his radio transmitter.
Owens called out, “Tricuspid valve ahead.”
The others looked ahead. At the end of a long, long corridor, they could see it in the far distance. Three sparkling red sheets, separating and billowing open as they moved away from the ship. An aperture yawned and grew larger while the cusps of the valve fluttered each to its respective side. There beyond it was the right ventricle, one of the two main chambers.
The bloodstream moved into the cavity as though being pulled by a powerful suction. The Proteus moved with it so that the aperture approached and enlarged at a tremendous rate. The current was smooth, however, and the ship rode it with scarcely a tremor.
Then came the sound of the thunderous boom of the ventricles, the main, muscular chambers of the heart, as they contracted in systole. The leaves of the tricuspid valve ballooned back toward the ship, moving slowly shut, with a wet, smacking contact that closed the wall ahead into a long vertical furrow that parted into two above.
It was the right ventricle that lay on the other side of the now-closed valve. As that ventricle contracted, the blood could not regurgitate through the atrium and was forced instead into and through the pulmonary artery.
Grant called out above the reverberating boom. “One more heartbeat and that will be the last, they say.”
Michaels said, “It had better be, or it’s our last heartbeat, too. Shove on through, full speed, Owens, the instant the valve opens again.”
There was firm determination in his face now, Grant noted absently—no fear at all.
The radioactive sensors that had hovered about Benes’ head and neck were now clustered over his chest, over a region from which the thermal blanket had been folded back.
The charts of the circulating system on the wall had expanded now in the region of the heart and showed only part of the heart—the right atrium. The blip that marked the position of the Proteus had moved smoothly down the vena cava into the lightly muscled atrium which had expanded as they entered, then contracted.
The ship had, in one bound, been pushed nearly the length of the atrium toward the tricuspid valve, which closed just as they were at its brink. On an oscilloscopic scanner, each heartbeat was being translated into a wavering electronic beam and it was watched narrowly.
The electroshock apparatus was in position; and the electrodes hovered over Benes’ breast.
The final heartbeat began. The electron beam on the oscilloscope began moving upward. The left ventricle was relaxing for another intake of blood and as it relaxed the tricuspid valve would open.
“Now,” cried the technician at the heart indicator.
The two electrodes came down upon the chest, a needle on one of the dials of the heart console swung instantly into t
he red and a buzzer sounded urgently. It was flipped into silence. The oscilloscope record flattened out.
The message went up to the control tower in all its final simplicity, “Heartbeat stopped.”
Carter grimly clicked the stopwatch in his hands and the seconds began ticking off with unbearable speed.
Five pairs of eyes looked forward at the tricuspid valve. Owens’ hand was set for acceleration. The ventricle was relaxing and the semilunar valve at the end of the pulmonary artery, somewhere in there, must be creaking shut. No blood could return to the ventricle from the artery; the valve made sure of that. The sound of its closing filled the air with an unbearable vibration.
And as the ventricle continued to relax, blood had to enter from another direction—from the right atrium. The tricuspid valve, facing in the other direction, began to flutter open.
The mighty puckered crack ahead began to broaden, to make a corridor, a larger corridor, a vast opening.
“Now,” shouted Michaels. “Now! Now!”
His words were lost in the heartbeat and in the rise of the engines. The Proteus shot forward, through the opening and into the ventricle. In a few seconds, that ventricle would contract and in the furious turbulence that would follow the ship would be crushed like a matchbox and they would all be dead—and three-quarters of an hour later Benes would be dead.
Grant held his breath. The diastolic beat rumbled into silence and now—Nothing!
A deadly silence had fallen.
Duval cried, “Let me see!”
He was up the ladder and his head emerged into the bubble, the one spot within the ship from which a clear, unobstructed view to the rear was possible.
“The heart has stopped,” he cried. “Come and see.”
Cora took his place, and then Grant.
The tricuspid valve hung half open and limp. On its inner surface were the tremendous connective fibers that bound it to the inner surface of the ventricle; fibers that pulled the valve leaves back when the ventricle relaxed; and that held them firmly in position, when the contraction of the ventricle forced them together, preventing those leaves from pushing through altogether and making a reversed opening.
